Engine Controls & Fuel - 3.5l - Diagnosis & Troubleshooting Chevrolet Malibu VI рестайлинг

Symptoms Description

Symptoms covers conditions that are not covered by DTCs. Certain conditions can cause multiple symptoms. These conditions are listed together under Symptoms Testing. Conditions that may only cause specific symptoms are listed separately under Additional Symptoms Testing. Perform the Symptoms Testing before using the Additional Symptoms Testing.

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle before using the symptoms procedures.

Symptoms Verification

Before using the Symptom tables, perform the following inspections

1. Ensure that the engine control module (ECM) and malfunction indicator lamp (MIL) are operating correctly.
2. Ensure that there are no diagnostic trouble codes (DTCs) that are stored.
3. Ensure that the scan tool data is within a normal operating range. Refer to «Scan Tool Data List»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-data-list) .
4. Verify the customer concern.
5. Perform the Visual/Physical Inspection in this information. The visual/physical inspection is extremely important, and can lead to correcting a condition without additional testing. It may also help reveal the cause of an intermittent condition.

Identifying Intermittent Conditions

Many intermittent conditions occur with harness or connector movement due to engine torque, rough pavement, vibration or physical movements of a component. Refer to the following for a list of issues that may cause an intermittent condition

1. Moisture and water intrusion in connectors, terminals, and components
2. Incomplete connector mating
3. Poor terminal contact
4. High circuit or component resistance-High resistance can include any resistance, regardless of the amount, which can interrupt the operation of the component.
5. Harness that is too short or tight.
6. Wire insulation that is chaffed or cut.
7. High or low ambient temperature
8. High or low engine coolant temperatures
9. High underhood temperatures
10. Heat build up in component or circuit due to circuit resistance, poor terminal contact, or high electrical load
11. High or low system voltage
12. High vehicle load conditions
13. Rough road surfaces
14. Electro-magnetic interference (EMI)/circuit interference from relays, solenoids or other electrical surge
15. Incorrect installation of aftermarket, add on accessories

Visual/Physical Check

1. Ensure that the control module grounds are clean, tight, and correctly located. Refer to «Power and Grounding Schematic Icons»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-introduction__power-and-grounding-schematic-icons) and «Power and Grounding Connector End Views»(/chevrolet/malibu/vi-2006-2008/remont/electrical-component-locations/#wiring-systems-power-management-component-locator-component-views-and-power-ground-and-inline-harness-connector-views) .
2. Ensure that the vacuum hoses are not split, kinked, and properly connected, as shown on the Vehicle Emission Control Information label. Refer to «EMISSION HOSE ROUTING DIAGRAM»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-22l-l61-introduction-2-of-2) . Refer to «Evaporative Emissions Hose Routing Diagram»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2) .
3. Ensure that the air filter is clean and free from restrictions.
4. Ensure that there is no water intrusion in connectors terminals and components.
5. Inspect the air intake ducts for the following conditions: Collapsed Damaged areas Looseness Incorrect installation Leaking
6. Inspect for air leaks at the throttle body mounting area, the mass air flow (MAF) sensor and intake manifold sealing surfaces.
7. Inspect the wiring harness for the following conditions: Poor connections Pinches Cuts
8. Inspect for loose, damaged, unseated, or missing sensors/components.
9. Inspect the terminals for corrosion and correct contact.

Symptoms Testing

Backfire, Cuts Out/Misses, Detonation/Spark Knock, Dieseling/Run-On, Hard Start, Hesitation/Sag/Stumble, Lack of Power/Sluggishness/Sponginess, Poor Fuel Economy, Rough, Unstable, or Incorrect Idle and Stalling, or Surges/Chuggles

1. Test the fuel system for the following: The fuel system for correct operation volume and pressure. Refer «Fuel System Diagnosis»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting) . The fuel injectors for proper operation. Refer to «Fuel Injector Diagnosis (w/J39021 or w/Tech 2)»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting) or «Fuel Injector Diagnosis (w/CH47976)»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting) . The fuel quality condition. Refer to «Alcohol/Contaminants-in-Fuel Diagnosis»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting) .
2. Test ignition system for the following: Proper ignition system operation. Refer to «Electronic Ignition (EI) System Diagnosis»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting) . Spark plugs. Refer to «Spark Plug Inspection»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2__spark-plug-inspection) . Spark plugs for correct application. Refer to «Ignition System Specifications»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2__ignition-system-specifications) .
3. Inspect for the following conditions The proper operation of the transmission torque converter clutch (TCC). The scan tool should indicate an engine speed drop when the TCC is commanded ON. Refer to «Torque Converter Diagnosis»(/chevrolet/malibu/vi-2006-2008/remont/automatic-trans/#how-to-diagnosis-troubleshooting-the-automatic-transaxle-4t45-e-service__torque-converter-diagnosis) . The proper operation of the A/C compressor. Items that can cause an engine to run lean or rich. Refer to «DTC P0171, P0172, P0174, or P0175»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-dtc-p0010-to-dtc-p0336) . The crankshaft position (CKP) sensor for proper operation The proper operation of the knock sensor (KS) system Inspect the exhaust system. Refer to «Symptoms - Engine Exhaust»(/chevrolet/malibu/vi-2006-2008/remont/exhaust/#engine-exhaust-system__symptoms-engine-exhaust) . Electromagnetic interference (EMI) on the reference circuit can cause a misfire condition. You can usually detect EMI with a scan tool by monitoring the engine speed parameter. A sudden increase in the engine speed parameter with little change in actual engine speed indicates that EMI is present. Inspect the high voltage components near the ignition control circuit if a condition exists. The crankcase ventilation valve for proper operation. The proper operation of the evaporative emission (EVAP) canister purge solenoid. The proper operation of the engine cooling system. Refer to «Symptoms - Engine Cooling»(/chevrolet/malibu/vi-2006-2008/remont/cooling-system-mechanical/#engine-cooling-system) .
4. Inspect the engine for the following mechanical failures: Refer to «Symptoms - Engine Mechanical»(/chevrolet/malibu/vi-2006-2008/remont/mechanical/#engine-mechanical-35l) . Excessive oil in the combustion chamber or leaking valve seals Oil Consumption Incorrect cylinder compression Sticking or leaking valves Worn camshaft lobes Incorrect valve timing Worn rocker arms Broken valve springs Excessive carbon buildup in the combustion chambers-Clean the chambers with top engine cleaner. Follow the instructions on the can. Incorrect engine parts
5. If the above conditions do not address the symptom, refer to the additional symptoms tests.

Additional Symptoms Tests

Hard Start

1. Verify that the engine coolant temperature (ECT) has not shifted in value. Refer to «Temperature Versus Resistance»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-22l-l61-introduction-2-of-2__temperature-versus-resistance) .
2. Verify the engine electrical system for correct operation. Refer to «Symptoms - Engine Electrical»(/chevrolet/malibu/vi-2006-2008/remont/charging-system/#battery-charging-system-and-starting-system__symptoms-engine-electrical) .
3. Verify that the driver is using the correct starting procedure as described in the owners manual.
4. Verify that there is adequate fuel.
5. Inspect for excessive crankshaft endplay that will cause the crankshaft position (CKP) sensor reluctor wheel to move out of alignment with the CKP sensor. Refer to «Crankshaft and Bearings Cleaning and Inspection»(/chevrolet/malibu/vi-2006-2008/remont/mechanical/#engine-mechanical-35l__crankshaft-and-bearings-cleaning-and-inspection) . IMPORTANT: A vehicle with a camshaft actuator stuck in an un-parked position may experience a hard start.
6. Start and run the vehicle until fully warm. Observe the camshaft position (CMP) variation parameter while accelerating up to 1,500 RPM and back to idle several times. The CMP variation should indicate a value for 1-2 seconds, then return to 0 degree. If the camshaft actuator does not respond, refer to «Camshaft Position Actuator Cleaning and Inspection»(/chevrolet/malibu/vi-2006-2008/remont/mechanical/#engine-mechanical-35l__camshaft-position-actuator-cleaning-and-inspection) and «Camshaft Position Actuator Magnet Cleaning and Inspection»(/chevrolet/malibu/vi-2006-2008/remont/mechanical/#engine-mechanical-35l__camshaft-position-actuator-magnet-cleaning-and) .

Hesitation, Sag, Stumble

1. Inspect the mass air flow (MAF) sensor for obstruction, contamination, and damage. Refer to «Throttle Body Assembly Replacement»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2) .
2. Test the generator. Refer to «Symptoms - Engine Electrical»(/chevrolet/malibu/vi-2006-2008/remont/charging-system/#battery-charging-system-and-starting-system__symptoms-engine-electrical) . Repair the charging system if the generator output voltage is less than 9 volts or more than 16 volts.
3. Inspect for excessive crankshaft endplay that will cause the crankshaft position (CKP) sensor reluctor wheel to move out of alignment with the CKP sensor. Refer to «Crankshaft and Bearings Cleaning and Inspection»(/chevrolet/malibu/vi-2006-2008/remont/mechanical/#engine-mechanical-35l__crankshaft-and-bearings-cleaning-and-inspection) .

Poor Fuel Economy

1. Heavy loads being carried or towed
2. Acceleration rate too much or too often
3. Inspect the brake system for brake drag.
4. Inspect for incorrect operation of the speedometer.
5. Verify that the engine coolant temperature (ECT) has not shifted in value. Refer to «Temperature Versus Resistance»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-22l-l61-introduction-2-of-2__temperature-versus-resistance) .
6. Inspect the mass air flow (MAF) sensor for obstruction, contamination, and damage. Refer to «Throttle Body Assembly Replacement»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2) .
7. Inspect for foreign material accumulation in the throttle bore, and for carbon deposits on the throttle plate and shaft. Also inspect for throttle body tampering. IMPORTANT: A vehicle with a camshaft actuator either stuck at full camshaft retard, in the Park position, or uncontrolled and wandering, may experience poor fuel economy.
8. Start and run the vehicle until fully warm. Observe the CMP variation parameter while accelerating up to 1,500 RPM and back to idle several times. The CMP variation should indicate a value for 1-2 seconds, then return to 0 degree. If the camshaft actuator responds erratic, inconsistent, or not at all, refer to «Camshaft Position Actuator Magnet Cleaning and Inspection»(/chevrolet/malibu/vi-2006-2008/remont/mechanical/#engine-mechanical-35l__camshaft-position-actuator-magnet-cleaning-and) and «Camshaft Position Actuator Cleaning and Inspection»(/chevrolet/malibu/vi-2006-2008/remont/mechanical/#engine-mechanical-35l__camshaft-position-actuator-cleaning-and-inspection) .

Detonation/Spark Knock

1. Test for an engine overheating condition. Refer to «Symptoms - Engine Cooling»(/chevrolet/malibu/vi-2006-2008/remont/cooling-system-mechanical/#engine-cooling-system) .
2. Verify that the engine coolant temperature (ECT) has not shifted in value. Refer to «Temperature Versus Resistance»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-22l-l61-introduction-2-of-2__temperature-versus-resistance) .
3. If there are no engine mechanical faults, fill the fuel tank with a known high quality fuel that meets the vehicle minimum octane requirements.

Lack of Power, Hesitation, or Cut Out

1. Inspect the engine electrical system for correct operation. Refer to «Symptoms - Engine Electrical»(/chevrolet/malibu/vi-2006-2008/remont/charging-system/#battery-charging-system-and-starting-system__symptoms-engine-electrical) .
2. Verify that each injector harness is connected to the correct injector.
3. Inspect the mass air flow (MAF) sensor for obstruction, contamination, and damage. Refer to «Throttle Body Assembly Replacement»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2) . IMPORTANT: A vehicle with a camshaft actuator stuck in the Park position may experience a lack of power during take-off.
4. Start and run the vehicle until fully warm. Observe the CMP variation parameter while accelerating up to 1,500 RPM and back to idle several times. The CMP variation should indicate a value for 1-2 seconds, then return to 0 degree. If the camshaft actuator does not respond, refer to «Camshaft Position Actuator Cleaning and Inspection»(/chevrolet/malibu/vi-2006-2008/remont/mechanical/#engine-mechanical-35l__camshaft-position-actuator-cleaning-and-inspection) and «Camshaft Position Actuator Magnet Cleaning and Inspection»(/chevrolet/malibu/vi-2006-2008/remont/mechanical/#engine-mechanical-35l__camshaft-position-actuator-magnet-cleaning-and) .

Rough, Unstable, or Incorrect Idle and Stalling

1. Inspect the mass air flow (MAF) sensor for obstruction, contamination, and damage. Refer to «Throttle Body Assembly Replacement»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2) .
2. Inspect the engine mounts. Refer to «Engine Mount Inspection»(/chevrolet/malibu/vi-2006-2008/remont/mechanical/#engine-mechanical-35l__engine-mount-inspection) .
3. Inspect the intake and exhaust manifolds for casting flash.

Surges/Chuggles

1. Inspect the mass air flow (MAF) sensor for obstruction, contamination, and damage. Refer to «Throttle Body Assembly Replacement»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2) .
2. Test the heated oxygen sensors (HO2S). The HO2S should respond quickly to a change in throttle position. If the HO2S do not respond to different throttle positions, inspect for contamination from fuel, silicon, or the incorrect use of RTV sealant. The sensors may have a white powdery coating and result in a high, but false, signal voltage, which gives a rich exhaust indication. The ECM reduces the amount of fuel delivered to the engine, causing a driveability condition.
3. Verify that each injector harness is connected to the correct injector. IMPORTANT: A vehicle with a camshaft actuator uncontrolled and wandering may experience an engine surge.
4. Start and run the vehicle until fully warm. Observe the CMP variation parameter while accelerating up to 1,500 RPM and back to idle several times. The CMP variation should indicate a value for 1-2 seconds, then return to 0 degree. If the camshaft actuator does not respond, refer to «Camshaft Position Actuator Cleaning and Inspection»(/chevrolet/malibu/vi-2006-2008/remont/mechanical/#engine-mechanical-35l__camshaft-position-actuator-cleaning-and-inspection) and «Camshaft Position Actuator Magnet Cleaning and Inspection»(/chevrolet/malibu/vi-2006-2008/remont/mechanical/#engine-mechanical-35l__camshaft-position-actuator-magnet-cleaning-and) .

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Circuit/System Description

Ignition voltage is supplied to the malfunction indicator lamp (MIL). The engine control module (ECM) turns the MIL ON by grounding the MIL control circuit.

Reference Information

Schematic Reference

1. «Instrument Cluster Schematics»(/chevrolet/malibu/vi-2006-2008/remont/gauges-instrument-panels/#instrument-panel-system-displays-and-gauges)
2. «Engine Controls Schematics»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2)

Connector End View Reference

1. «Displays and Gages Connector End Views»(/chevrolet/malibu/vi-2006-2008/remont/gauges-instrument-panels/#instrument-panel-system-displays-and-gauges)
2. «Engine Control Module Connector End Views»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2)

Electrical Information Reference

1. «Circuit Testing»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__circuit-testing)
2. «Connector Repairs»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__wiring-repairs)

Scan Tool Reference

1. «Scan Tool Data List»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-data-list)
2. «Scan Tool Data Definitions»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-data-definitions)
3. «Scan Tool Output Controls»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-output-controls)

Circuit/System Verification

Ignition ON, the MIL should turn ON and OFF when commanded with a scan tool.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the instrument panel cluster (IPC).
2. Ignition ON, verify that a test lamp illuminates between the ignition circuit and ground. If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition circuit fuse is open, replace the IPC.
3. Connect a test lamp between the control circuit and the ignition circuit.
4. Command the MIL ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states. If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the ECM. If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
5. If all circuits test normal, replace the IPC.

Repair Procedures

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Control Module References»(/chevrolet/malibu/vi-2006-2008/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for ECM replacement, setup, and programming
2. «Instrument Cluster Replacement»(/chevrolet/malibu/vi-2006-2008/remont/gauges-instrument-panels/#instrument-panel-system-displays-and-gauges)

Diagnostic Instructions

1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/malibu/vi-2006-2008/remont/oem-general-information/#vehicle-diagnostic-information__diagnostic-system-check-vehicle)
2. «Strategy Based Diagnosis»(/chevrolet/malibu/vi-2006-2008/remont/oem-general-information/#vehicle-diagnostic-information__strategy-based-diagnosis)
3. «Diagnostic Procedure Instructions»(/chevrolet/malibu/vi-2006-2008/remont/oem-general-information/#vehicle-diagnostic-information__diagnostic-procedure-instructions)

This Engine Cranks but Does Not Run is an organized approach to identify a condition which causes the engine to crank but not start. This diagnostic directs the technician to the appropriate system diagnosis.

This diagnostic assumes the system voltage levels are adequate for starter motor operation. Refer to Battery Inspection/Test , and Engine Cranks Slowly . Fuel level and fuel quality should be determined for correct diagnosis.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

1. «Engine Control Module Connector End Views»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2)
2. «Engine Controls Connector End Views»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2)
3. «Electrical Center Identification Views»(/chevrolet/malibu/vi-2006-2008/remont/electrical-component-locations/#wiring-systems-power-management-component-locator-component-views-and-power-ground-and-inline-harness-connector-views)

Electrical Information Reference

1. «Circuit Testing»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__circuit-testing)
2. «Connector Repairs»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__wiring-repairs)
5. «Starting System Description and Operation»(/chevrolet/malibu/vi-2006-2008/remont/charging-system/#battery-charging-system-and-starting-system__starting-system-description-and-operation)

Scan Tool Reference

1. «Scan Tool Data List»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-data-list)
2. «Scan Tool Data Definitions»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-data-definitions)
3. «Scan Tool Output Controls»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-output-controls)

Special Tools Required

1. CH-48027 Digital Pressure Gage
2. J 26792 HEI Spark Tester

Attempt to start the engine. The engine should start and run.

1. Crank the engine for up to 30 seconds.
2. Observe the vehicle DTC information with a scan tool. If any of the following DTCs are set, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/chevrolet/malibu/vi-2006-2008/remont/oem-general-information/#vehicle-diagnostic-information__diagnostic-trouble-code-dtc-list) to diagnose those DTCs: P0016, P0201-P0206, P0335, P0336, P0351-P0353, P0601, P0602, P0603, P0604, P0606, P0607, P060D, P062F, P0685, P0689, P0690, P1516, P1682, P2610
3. Ignition ON, verify the scan tool injector circuit status parameters indicate Incomplete. If the parameters do not indicate Incomplete, refer to «DTC P0201, P0202, P0203, P0204, P0205, or P0206»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-dtc-p0010-to-dtc-p0336) .
4. Observe the engine speed parameter while cranking the engine. If engine RPM is not indicated, refer to «DTC P0335 or P0336»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-dtc-p0010-to-dtc-p0336) .
5. Install a J 26792 .
6. Crank the engine for 15 seconds. Spark should be observed from the J 26792 . If spark is not observed, refer to «Electronic Ignition (EI) System Diagnosis»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting) .
7. With the ignition ON and the engine OFF, test the fuses that are supplied by the powertrain relay for voltage. The test lamp should illuminate at each test point for the following fuses: Emission Fuse Ignition 1 Fuse If the test lamp does not illuminate on at least one side of each fuse, refer to «DTC P0685, P0689, or P0690»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-dtc-p0340-to-dtc-p2544) . IMPORTANT: Additional DTCs may set when using the fuel pump output control.
8. Command the fuel pump ON and OFF. Fuel pump should energize when commanded ON and De-energize when commanded OFF. If the fuel pump does not respond, refer to «Fuel Pump Electrical Circuit Diagnosis»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting) .
9. Turn OFF the ignition.
10. Install the CH-48027 Digital Pressure Gage. Turn ON the ignition and command the fuel pump ON while observing the CH-48027 . The fuel pressure should be between 384-425 kPa (56-62 psi). If the fuel pressure is not within 384-425 kPa (56-62 psi), refer to «Fuel System Diagnosis»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting) .
11. Inspect for the following conditions: Compare the actual engine coolant temperature to the ECT parameter. Air filter and air intake system for restrictions and obstructions Test the fuel for contamination. Refer to «Alcohol/Contaminants-in-Fuel Diagnosis»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting) . Inspect the spark plug and spark plug wires. Refer to «Spark Plug Inspection»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2__spark-plug-inspection) and «Spark Plug Wire Inspection»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2__spark-plug-wire-inspection) . Test the exhaust system for restrictions. Refer to «Restricted Exhaust»(/chevrolet/malibu/vi-2006-2008/remont/exhaust/#engine-exhaust-system) .

Repair Verification

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Fuel Pump Electrical Circuit Diagnosis

The control module enables the fuel pump relay when the ignition switch is turned ON. The control module will disable the fuel pump relay within 2 seconds unless the control module detects ignition reference pulses. The control module continues to enable the fuel pump relay as long as ignition reference pulses are detected. The control module disables the fuel pump relay within 2 seconds if ignition reference pulses cease to be detected and the ignition remains ON.

Diagnostic Aids

The following conditions may cause the fuel pump fuse to open

1. The fuse is faulty.
2. There is an intermittent short to ground in the supply voltage circuit of the fuel pump.
3. The fuel pump has an intermittent internal condition.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

1. ECM Connector End Views
2. «Engine Controls Connector End Views»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2)
3. «Electrical Center Identification Views»(/chevrolet/malibu/vi-2006-2008/remont/electrical-component-locations/#wiring-systems-power-management-component-locator-component-views-and-power-ground-and-inline-harness-connector-views)

Electrical Information Reference

1. «Circuit Testing»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__circuit-testing)
2. «Connector Repairs»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__wiring-repairs)

Scan Tool Reference

1. «Scan Tool Data List»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-data-list)
2. «Scan Tool Data Definitions»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-data-definitions)
3. «Scan Tool Output Controls»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-output-controls)

Special Tools Required

J 43244 Relay Puller Pliers

1. With the ignition ON, engine OFF, command the fuel pump relay ON and OFF several times using the scan tool output control function. You should either hear or feel the relay click and the fuel pump should turn ON and OFF with each command. If the fuel pump operates continuously, test for a faulty relay or a short to voltage in the supply voltage circuit of the fuel pump.

1. With the ignition OFF, remove the fuel pump relay from the rear electrical center.
2. With the ignition ON, engine OFF, probe the control circuit of the fuel pump relay with a test lamp that is connected to a good ground. Command the fuel pump relay ON and OFF with a scan tool. The test lamp should turn ON and OFF with each command. If the test lamp does not turn ON and OFF, test for an open or a short to ground in the fuel pump relay control circuit, or an intermittent or a poor connection at the engine control module (ECM). If the circuit tests normal, replace the control module. If the test lamp remains illuminated with each command, test for a short to voltage in the control circuit of the fuel pump relay, or an intermittent or a poor connection at the ECM. If the circuit tests normal, replace the control module.
3. Connect a test lamp between the control circuit of the fuel pump relay and the ground circuit of the fuel pump relay. Command the fuel pump relay ON and OFF with a scan tool. If the test lamp does not turn ON and OFF, repair the open or the high resistance in the ground circuit of the fuel pump relay. If the test lamp does turn ON and OFF, test for an intermittent and for a poor connection at the fuel pump relay, or a faulty fuel pump relay.
4. Inspect the fuel pump fuse. If the fuel pump fuse is open, test for a short to ground in the supply voltage circuit of the fuel pump, or a faulty fuel sender.
5. With the ignition ON, engine OFF, probe the battery positive voltage circuit of the fuel pump relay with a test lamp that is connected to a good ground. If the test lamp does not illuminate, repair the open in the battery positive voltage circuit.
6. Connect a 15-amp fused jumper wire between the battery positive voltage circuit of the fuel pump relay and the supply voltage circuit of the fuel pump. If the fuel pump operates, test for an intermittent or poor connection at the fuel pump relay, or a faulty fuel pump relay. If the fuel pump does not operate, test for an open or high resistance in the supply voltage circuit of the fuel pump, an open or high resistance in the ground circuit of the fuel pump, an intermittent or poor connection at the fuel sender cover, or a faulty fuel sender.

Component Testing

1. Measure for 70-110 ohms of resistance between terminals 85 and 86 of the fuel pump relay. If the resistance is not within the specified range, replace the fuel pump relay.
2. Measure for infinite resistance between the following terminals of the fuel pump relay: 30 and 86 30 and 87 30 and 85 85 and 87 If continuity is detected, replace the fuel pump relay.
3. Connect a 20-amp fused jumper wire from the positive terminal of the battery to relay terminal 85. Connect a jumper wire from the negative terminal of the battery to relay terminal 86. Measure for less than 2 ohms between terminals 30 and 87 of the relay. If the resistance measures more than 2 ohms, replace the fuel pump relay.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Control Module References»(/chevrolet/malibu/vi-2006-2008/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for ECM replacement, setup, and programming
2. «Fuel Tank Pressure Sensor Replacement (Sedan)»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2) or «Fuel Tank Pressure Sensor Replacement (Maxx)»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2)
3. Relay Replacement

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

The control module enables the fuel pump relay when the ignition switch is turned ON. The control module will disable the fuel pump relay within 2 seconds unless the control module detects ignition reference pulses. The control module continues to enable the fuel pump relay as long as ignition reference pulses are detected. The control module disables the fuel pump relay within 2 seconds if ignition reference pulses cease to be detected and the ignition remains ON.

The fuel system is a returnless on-demand design. The fuel pressure regulator is a part of the fuel sender assembly, eliminating the need for a return pipe from the engine. A returnless fuel system reduces the internal temperature of the fuel tank by not returning hot fuel from the engine to the fuel tank. Reducing the internal temperature of the fuel tank results in lower evaporative emissions.

The fuel tank stores the fuel supply. An electric turbine style fuel pump attaches to the fuel sender assembly inside the fuel tank. The fuel pump supplies high pressure fuel through the fuel filter, contained in the fuel sender assembly, and the fuel feed pipe to the fuel injection system. The fuel pump provides fuel at a higher rate of flow than is needed by the fuel injection system. The fuel pump also supplies fuel to a venturi pump located on the bottom of the fuel sender assembly. The function of the venturi pump is to fill the fuel sender assembly reservoir. The fuel pressure regulator, a part of the fuel sender assembly, maintains the correct fuel pressure to the fuel injection system. The fuel pump and sender assembly contains a reverse flow check valve. The check valve and the fuel pressure regulator maintain fuel pressure in the fuel feed pipe and the fuel rail in order to prevent long cranking times.

Electrical Information Reference

1. «Circuit Testing»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__circuit-testing)
2. «Connector Repairs»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__wiring-repairs)

Scan Tool Reference

1. «Scan Tool Data List»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-data-list)
2. «Scan Tool Data Definitions»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-data-definitions)
3. «Scan Tool Output Controls»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-output-controls)

Special Tools Required

1. Install Fuel Pressure Gauge Fuel Pressure Gage
2. J 37287 Fuel Line Shut-off Adapter

1. Turn ON the ignition, with the engine OFF.
2. Command the fuel pump relay ON with a scan tool. If the fuel pump does not operate, refer to «Fuel Pump Electrical Circuit Diagnosis»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting) .
3. Turn OFF the ignition.
4. Turn OFF all accessories.
5. Install a Fuel Pressure Gauge. Refer to «Fuel Pressure Gage Installation and Removal»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-22l-l61-introduction-2-of-2) .
6. Turn ON the ignition, with the engine OFF. IMPORTANT: The fuel pump relay may need to be commanded ON a few times in order to obtain the highest possible fuel pressure. DO NOT start the engine.
7. Command the fuel pump relay ON with a scan tool.
8. Observe the Fuel Pressure Gauge with the fuel pump commanded ON. The fuel pressure should be 345-414 kPa (50-60 psi). If the fuel pressure is less than 345 kPa (50 psi), inspect for a restricted fuel feed pipe, poor connections at the harness connectors and ground circuits of the fuel pump, or a faulty fuel sender assembly. If the fuel pressure is more than 414 kPa (60 psi), replace the fuel sender assembly. IMPORTANT: The fuel pressure may vary slightly when the fuel pump stops operating. After the fuel pump stops operating, the fuel pressure should stabilize and remain constant.
9. Monitor the Fuel Pressure Gauge for 1 minute. The fuel pressure should not decrease more than 34 kPa (5 psi). If the fuel pressure decreases more than 34 kPa (5 psi), continue with Circuit/System Testing.
10. Relieve the fuel pressure to 69 kPa (10 psi).
11. Monitor the Fuel Pressure Gauge for 5 minutes. The fuel pressure should not decrease more than 14 kPa (2 psi). If the fuel pressure decreases more than 14 kPa (2 psi), replace the fuel sender assembly.
12. Remove the Fuel Pressure Gauge. Refer to «Fuel Pressure Gage Installation and Removal»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-22l-l61-introduction-2-of-2) .
13. Operate the vehicle within the conditions to reproduce the original symptoms.
14. Monitor the O2 and the Fuel Trim parameters with a scan tool. If the scan tool parameters indicate a lean condition, inspect for a restricted fuel feed pipe, poor connections at the harness connectors and ground circuits of the fuel pump, or a faulty fuel sender assembly. If the scan tool parameters do not indicate a lean condition, go to «Symptoms - Engine Controls»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting) .

1. Turn OFF the ignition.
2. Relieve the fuel pressure. Refer to «Fuel Pressure Relief»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-22l-l61-introduction-2-of-2__fuel-pressure-relief) .
3. Disconnect the chassis fuel hose from the engine compartment fuel pipe. Refer to «Metal Collar Quick Connect Fitting Service»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2) .
4. Install the J 37287 between the chassis fuel hose and the engine compartment fuel pipe.
5. Open the valve on the J 37287 .
6. Turn ON the ignition, with the engine OFF.
7. Command the fuel pump relay ON with a scan tool.
8. Bleed the air from the Fuel Pressure Gauge.
9. Command the fuel pump relay ON and then OFF with a scan tool.
10. Close the fuel feed pipe shut-off valve.
11. Monitor the Fuel Pressure Gauge for 1 minute. If the fuel pressure remains constant, replace the fuel sender assembly. If the fuel pressure does not remain constant, locate and replace the leaking fuel injectors.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Fuel Pump Module Replacement (Sedan)»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2) or «Fuel Pump Module Replacement (Maxx)»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2)
2. «Fuel Rail Assembly Replacement»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2)
3. «Fuel Injector Replacement»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2)

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

The control module enables the appropriate fuel injector pulse for each cylinder. The ignition voltage is supplied directly to the fuel injectors. The control module controls each fuel injector by grounding the control circuit via a solid state device called a driver. A fuel injector coil winding resistance that is too high or too low will affect the engine driveability. A fuel injector control circuit DTC may not set, but a misfire may be apparent. The fuel injector coil windings are affected by temperature. The resistance of the fuel injector coil windings will increase as the temperature of the fuel injector increases.

When performing the fuel injector balance test, the scan tool is first used to energize the fuel pump relay. The fuel injector tester or the scan tool is then used to pulse each injector for a precise amount of time, allowing a measured amount of the fuel to be injected. This causes a drop in the system fuel pressure that can be recorded and used to compare each injector.

1. Monitoring the misfire current counters, or misfire graph, may help to isolate the fuel injector that is causing the condition.
2. Operating the vehicle over a wide temperature range may help isolate the fuel injector that is causing the condition.
3. Perform the fuel injector coil test within the conditions of the customer's concern. A fuel injector condition may only be apparent at a certain temperature, or under certain conditions.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

1. «Engine Controls Connector End Views»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2)
2. «Inline Harness Connector End Views»(/chevrolet/malibu/vi-2006-2008/remont/electrical-component-locations/#wiring-systems-power-management-component-locator-component-views-and-power-ground-and-inline-harness-connector-views)
3. «Engine Control Module Connector End Views»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2)

Electrical Information Reference

1. «Circuit Testing»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__circuit-testing)
2. «Connector Repairs»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__wiring-repairs)

Scan Tool Reference

1. «Scan Tool Data List»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-data-list)
2. «Scan Tool Data Definitions»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-data-definitions)
3. «Scan Tool Output Controls»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-output-controls)

Special Tools Required

1. CH-48027 Digital Pressure Gage
2. J-39021-450 Fuel Injector Harness Adapter. See «Special Tools»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2__special-tools) .
3. J 39021 Fuel Injector Coil and Balance Tester

Fuel Injector Coil Test

1. Observe the ECT Sensor parameter with a scan tool. The ECT sensor should be 10-32°C (50-90°F). If the ECT Sensor parameter is not within 10-32°C (50-90°F), go to step 3.
2. Measure the resistance of each fuel injector with a DMM. The resistance of each fuel injector should be 11-14 ohms. If the resistance of any fuel injector is not 11-14 ohms, replace the fuel injector.
3. Measure and record the resistance of each fuel injector with a DMM. Subtract the lowest resistance value from the highest resistance value. The difference between the lowest value and the highest value should be equal to or less than 3 ohms. If the difference is equal to or less than 3 ohms, perform the Fuel Injector Balance Test-Fuel Pressure Test. If the difference is more than 3 ohms, continue with the Fuel Injector Coil Test.
4. Add all of the fuel injector resistance values to obtain a total resistance value. Divide the total resistance value by the number of fuel injectors to obtain an average resistance value. Subtract the lowest individual fuel injector resistance value from the average resistance value. Compute the difference between the highest individual fuel injector resistance value and the average resistance value. Replace the fuel injector that displays the greatest resistance difference above or below the average.
5. Perform the Fuel Injector Balance Test-Fuel Pressure Test.

Fuel Injector Balance Test-Fuel Pressure Test

1. Install a fuel pressure gage. Refer to «Fuel Pressure Gage Installation and Removal»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-22l-l61-introduction-2-of-2) .
2. Turn ON the ignition, with the engine OFF. IMPORTANT: The fuel pump relay may need to be commanded ON a few times in order to obtain the highest possible fuel pressure. DO NOT start the engine.
3. Command the fuel pump relay ON with a scan tool.
4. Observe the fuel pressure gage with the fuel pump commanded ON. The fuel pressure should be 384-425 kPa (56-62 psi). If the fuel pressure is not 384-425 kPa (56-62 psi), refer to «Fuel System Diagnosis»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting) .
5. Monitor the fuel pressure gage for one minute. The fuel pressure should not decrease more than 34 kPa (5 psi). If the fuel pressure decreases more than 34 kPa (5 psi), refer to «Fuel System Diagnosis»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting) .
6. Perform the Fuel Injector Balance Test with Special Tool or the Fuel Injector Balance Test with Tech 2.

Fuel Injector Balance Test with Special Tool

1. Set the amperage supply selector switch on the fuel injector tester to the Balance Test 0.5-2.5 amp position.
2. Disconnect the multi-way harness connector of the fuel injectors.
3. Connect the J 39021 , the J 39021-210 , and the J-39021-450 to the fuel injector multi-way connector. See «Special Tools»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2__special-tools) .
4. Command the fuel pump relay ON and then OFF three times with a scan tool. On the last command, as the fuel pressure begins to slowly degrade and stabilize, select a fuel pressure within 34 kPa (5 psi) of the maximum pump pressure. Record this fuel pressure. This is the starting pressure at which you will pulse each injector.
5. Command the fuel pump relay ON one more time and energize the fuel injector by depressing the Push to Start Test button on the J 39021 at the previously selected pressure.
6. After the injector stops pulsing, select Min from the Display Mode and record the Min pressure. IMPORTANT: New test results will not be recorded if the Min/Max results are not cleared after each injector is tested.
7. Clear the Min/Max results.
8. Select Normal from the Display Mode.
9. Repeat steps 3 and 5 through 8 for each fuel injector.
10. Perform the Pressure Drop Calculation.

Fuel Injector Balance Test with Tech 2

1. Command the fuel pump relay ON and then OFF three times with a scan tool. On the last command, as the fuel pressure begins to slowly degrade and stabilize, select a fuel pressure within 34 kPa (5 psi) of the maximum pump pressure. Record this fuel pressure. This is the starting pressure at which you will pulse each injector.
2. With a scan tool, select the Fuel Injector Balance Test function within the Special Functions menu.
3. Select an injector to be tested.
4. Press Enter to prime the fuel system.
5. Energize the fuel injector by depressing the Pulse Injector button on the scan tool at the previously selected pressure.
6. After the injector stops pulsing, select Min from the Display Mode on the CH-48027 and record the Min pressure. IMPORTANT: New test results will not be recorded if the Min/Max results are not cleared after each injector is tested.
7. Clear the Min/Max results on the CH-48027 .
8. Select Normal from the Display Mode on the CH-48027 .
9. Press Enter on the scan tool to bring you back to the Select Injector screen.
10. Repeat steps 3 through 9 for each fuel injector.
11. Perform the Pressure Drop Calculation.

Pressure Drop Calculation

1. Subtract the minimum pressure from the starting pressure for one fuel injector. The result is the pressure drop value.
2. Obtain a pressure drop value for each fuel injector.
3. Add all of the individual pressure drop values except for the injector suspected of being faulty. This is the total pressure drop.
4. Divide the total pressure drop by the number of fuel injectors that were added together. This is the average pressure drop. The difference between any individual pressure drop and the average pressure drop should not be more than 20 kPa (3 psi). If the difference between any individual pressure drop and the average pressure drop is more than 20 kPa (3 psi), replace the fuel injector.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Fuel Injector Replacement

1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/malibu/vi-2006-2008/remont/oem-general-information/#vehicle-diagnostic-information__diagnostic-system-check-vehicle)
2. «Strategy Based Diagnosis»(/chevrolet/malibu/vi-2006-2008/remont/oem-general-information/#vehicle-diagnostic-information__strategy-based-diagnosis)
3. «Diagnostic Procedure Instructions»(/chevrolet/malibu/vi-2006-2008/remont/oem-general-information/#vehicle-diagnostic-information__diagnostic-procedure-instructions)

The control module enables the appropriate fuel injector pulse for each cylinder. The ignition voltage is supplied directly to the fuel injectors. The control module controls each fuel injector by grounding the control circuit via a solid state device called a driver. A fuel injector coil winding resistance that is too high or too low will affect the engine driveability. A fuel injector control circuit DTC may not set, but a misfire may be apparent. The fuel injector coil windings are affected by temperature. The resistance of the fuel injector coil windings will increase as the temperature of the fuel injector increases.

The Active Fuel Injector Tester (AFIT), CH 47976, is used to test the fuel pump, fuel system leak down, and the fuel injectors. Following the User Guide, CH 47976-11, and the on screen prompts or selections, will indicate the steps required to perform each of the available tests. The tester will perform all of the tests automatically and display results of the test. The results can also be down loaded for storage and printing.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

1. «Engine Controls Connector End Views»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2)
2. «Inline Harness Connector End Views»(/chevrolet/malibu/vi-2006-2008/remont/electrical-component-locations/#wiring-systems-power-management-component-locator-component-views-and-power-ground-and-inline-harness-connector-views)

Electrical Information Reference

1. «Circuit Testing»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__circuit-testing)
2. «Connector Repairs»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__wiring-repairs)

Special Tools Required

CH 47976 Active Fuel Injector Tester

Fuel Injector Coil Test

1. Observe the ECT Sensor parameter with a scan tool. The ECT sensor should be 10-32°C (50-90°F). If the ECT Sensor parameter is not within 10-32°C (50-90°F), go to step 3.
2. Measure the resistance of each fuel injector with a DMM. The resistance of each fuel injector should be 11-14 ohms. If the resistance of any fuel injector is not 11-14 ohms, replace the fuel injector.
3. Measure and record the resistance of each fuel injector with a DMM. Subtract the lowest resistance value from the highest resistance value. The difference between the lowest value and the highest value should be equal to or less than 3 ohms. If the difference is equal to or less than 3 ohms, perform the AFIT Test Procedure. If the difference is more than 3 ohms, continue with the Fuel Injector Coil Test.
4. Add all of the fuel injector resistance values to obtain a total resistance value. Divide the total resistance value by the number of fuel injectors to obtain an average resistance value. Subtract the lowest individual fuel injector resistance value from the average resistance value. Compute the difference between the highest individual fuel injector resistance value and the average resistance value. Replace the fuel injector that displays the greatest resistance difference above or below the average.
5. Perform the AFIT Test Procedure.

AFIT Test Procedure

1. Turn OFF all accessories.
2. Turn OFF the ignition.
3. Install the AFIT. Refer to the AFIT User Guide.
4. Turn ON the AFIT and select the vehicle.
5. Turn ON the ignition and perform the Injector Test. If the AFIT aborts testing due to fuel pressure or fuel leak down, refer to «Fuel System Diagnosis»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting) .
6. View the test results. If any injector exceeds the recommended tolerance, replace the injector(s).

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Fuel Injector Replacement

Test Description

Water contamination in the fuel system may cause driveability conditions such as hesitation, stalling, no start, or misfires in one or more cylinders. Water may collect near a single fuel injector at the lowest point in the fuel injection system and cause a misfire in that cylinder. If the fuel system is contaminated with water, inspect the fuel system components for rust or deterioration.

Ethanol concentrations of greater than 10 percent can cause driveability conditions and fuel system deterioration. Fuel with more than 10 percent ethanol could result in driveability conditions such as hesitation, lack of power, stalling, or no start. Excessive concentrations of ethanol used in vehicles not designed for it may cause fuel system corrosion, deterioration of rubber components, and fuel filter restriction.

Special Tool

J 44175 Fuel Composition Tester

System Verification

The fuel sample should be drawn from the bottom of the tank so that any water present in the tank will be detected. The sample should be bright and clear.

1. If the sample appears cloudy, or contaminated with water, as indicated by a water layer at the bottom of the sample, perform the Particulate Contaminants in Fuel Testing Procedure.
2. If alcohol contamination is suspected, perform the Alcohol in Fuel Testing procedure.

Alcohol in Fuel Testing with Special Tool

1. Test the fuel composition using J 44175 and Instruction Manual.
2. If water appears in the fuel sample, clean the fuel system.
3. Subtract 50 from the reading on the DMM in order to obtain the percentage of alcohol in the fuel sample.
4. If the fuel sample contains more than 15 percent ethanol, add fresh, regular gasoline to the vehicles fuel tank.
5. Test the fuel composition.
6. If testing shows the ethanol percentage is still more than 15 percent, replace the fuel in the vehicle.

Alcohol in Fuel Testing without Special Tool

1. Using a 100 ml (3.38 oz) specified cylinder with 1 ml (0.034 oz) graduation marks, fill the cylinder with fuel to the 90 ml (3.04 oz) mark.
2. Add 10 ml (0.34 oz) of water in order to bring the total fluid volume to 100 ml (3.38 oz) and install a stopper.
3. Shake the cylinder vigorously for 10-15 seconds.
4. Carefully loosen the stopper in order to release the pressure.
5. Re-install the stopper and shake the cylinder vigorously again for 10-15 seconds.
6. Put the cylinder on a level surface for approximately 5 minutes in order to allow adequate liquid separation. If alcohol is present in the fuel, the volume of the lower layer, which would now contain both alcohol and water, will be more than 10 ml (0.34 oz). For example, if the volume of the lower layer is increased to 15 ml (0.51 oz), this indicates at least 5 percent alcohol in the fuel. The actual amount of alcohol may be somewhat more because this procedure does not extract all of the alcohol from the fuel.

Particulate Contaminants in Fuel Testing Procedure

1. Using an approved fuel container, draw approximately 0.5 liter (0.53 qt) of fuel.
2. Place the container on a level surface for approximately 5 minutes in order to allow settling of the particulate contamination. Particulate contamination will show up in various shapes and colors. Sand will typically be identified by a white or light brown crystals. Rubber will appear as black and irregular particles.
3. Observe the fuel sample. If any physical contaminants or water are present, clean the fuel system.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Fuel System Cleaning

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

There are 3 dual-tower ignition coils that are part of the ignition control module (ICM). The ICM contains coil driver circuits that command the coils to operate. The ICM has the following circuits

1. An ignition voltage circuit
2. A ground
3. An ignition control (IC) 1 control circuit for the 1-4 ignition coil
4. An IC 2 control circuit for the 2-5 ignition coil
5. An IC 3 control circuit for the 3-6 ignition coil
6. A low reference circuit

The engine control module (ECM) controls each dual-tower ignition coil by transmitting timing pulses on the ignition coil control circuit to the ICM for the proper coil to enable a spark event.

Inspect the spark plug wires for proper orientation.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

1. «Engine Control Module Connector End Views»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2)
2. «Engine Controls Connector End Views»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2)

Electrical Information Reference

1. «Circuit Testing»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__circuit-testing)
2. «Connector Repairs»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/chevrolet/malibu/vi-2006-2008/remont/ignition-switchsteering-lock/#wiring-systems-power-management-service-troubleshooting-diagnosis__wiring-repairs)

Scan Tool Reference

1. «Scan Tool Data List»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-data-list)
2. «Scan Tool Data Definitions»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-data-definitions)
3. «Scan Tool Output Controls»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-1-of-2__scan-tool-output-controls)

Special Tools Required

1. J 26792 Spark Tester
2. J 43244 Relay Puller Pliers

1. With the ignition OFF, remove the fuel pump relay using the J 43244 .
2. Crank the engine and test for a spark on each cylinder spark plug wire using the J 26792 . Ground the companion cylinder spark plug wire of each cylinder when it is tested. If a bright blue spark is present on all 6 of the cylinders, remove and inspect all of the spark plugs for proper torque, proper gap, wear, damage, and fouling. Refer to «Spark Plug Replacement»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2) and «Spark Plug Inspection»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2__spark-plug-inspection) . Replace the spark plugs if necessary. If there is no spark on any of the cylinders, test the ignition voltage circuit of the ICM for an open/high resistance or short to ground, or test the ground circuit of the ICM for an open/high resistance, or a faulty ICM. The wire circuit resistance should measure less than 3 ohms. If spark is present on one or more of the cylinders, inspect and test the spark plug wires for arching, cuts, rubbing on other components, and proper resistance, refer to «Spark Plug Wire Inspection»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2__spark-plug-wire-inspection) or a faulty ICM. If all tests are normal, then the system is operating correctly.

1. With positive polarity to the low reference terminal, measure for 9,000-11,000 ohms at 20-23°C (68-74°F) room temperature between each of the ignition coil control terminals and the low reference terminal of the ICM. If the resistance is not within the specified range, replace the ICM.
2. Measure for 7,000-15,000 ohms at 20-23°C (68-74°F) room temperature between each pair of coil towers on the ICM. If the resistance is not within the specified range, replace the ICM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Spark Plug Wire Replacement»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2) for spark plug wire replacement
2. «Spark Plug Replacement»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2) for spark plug replacement
3. «Ignition Coil Replacement»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-introduction-2-of-2) for ICM and coil assembly replacement

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Description

Several states require that a vehicle pass on-board diagnostic (OBD) system tests and the inspection/maintenance (I/M) emission inspection in order to renew license plates. This is accomplished by viewing the I/M System Status display on a scan tool. Using a scan tool, the technician can observe the I/M System Status in order to verify that the vehicle meets the criteria that comply with the local area requirements.

Conditions for Updating the I/M System Status

Each system monitor requires at least one, and sometimes several diagnostic tests. The result of each test is reported by a diagnostic trouble code (DTC). A system monitor is complete when either all of the DTCs composing the monitor have Run and Passed, or when any one of the DTCs comprising the monitor has illuminated the malfunction indicator lamp (MIL). Once the system monitor is complete, the I/M System Status display will indicate YES in the Completed column.

For example, when the HO2S Heater Status indicates YES, either all of the oxygen sensor heater tests have passed or one of the tests has illuminated the MIL. If the vehicle has four heated oxygen sensors, either all four heater circuit tests have passed or one of the heater circuit tests has illuminated the MIL. The I/M System Status will indicate NO under the Completed column when any of the required tests for that system have not run. The following is a list of conditions that would set the I/M System Status indicator to NO

1. The vehicle is new from the factory and has not yet been driven through the necessary drive conditions to complete the tests.
2. The battery has been disconnected or discharged below operating voltage.
3. The control module power or ground has been interrupted.
4. The control module has been reprogrammed.
5. The control module DTCs have been cleared.

Monitored Emission Control Systems

The OBD II System monitors all emission control systems that are on-board. The OBD II regulations require monitoring of the following

1. The air conditioning system
2. The catalytic converter efficiency
3. Comprehensive component monitoring-Emission related inputs and outputs
4. The evaporative emission (EVAP) system
5. The fuel delivery system
6. Heated catalyst monitoring
7. Misfire monitoring
8. The oxygen sensor system (O2S or HO2S)
9. The oxygen sensor heater system (HO2S heater)

For the specific DTCs required for each system, refer to Inspection/Maintenance (I/M) System DTC Table . Systems such as fuel delivery, misfire, and comprehensive components may not be listed in a system status list. These tests run continuously and do not require an I/M System Status indicator.

Review the I/M System Status indicators. All I/M System Status indicators should report YES.

1. Observe the Engine DTC information with a scan tool. If a DTC is set that would prevent the I/M System Status tests from completing, diagnose that DTC before continuing. Refer to «Inspection/Maintenance (I/M) System DTC Table»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting__inspectionmaintenance-im-system-dtc-table) .
2. Review applicable service bulletins for software updates that would prevent the I/M System Status tests from completing. If a control module re-program or other repair is required, perform the «Inspection/Maintenance (I/M) Complete System Set Procedure»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting) .
3. Observe the I/M System Status indicators. If any I/M System Status indicators report NO, perform the «Inspection/Maintenance (I/M) Complete System Set Procedure»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting) .

Perform the Inspection/Maintenance (I/M) System Check prior to using this diagnostic procedure.

The purpose of the inspection/maintenance (I/M) complete system set procedure is to satisfy the enable criteria necessary to execute all of the I/M readiness diagnostics and complete the trips for those particular diagnostics. When all I/M monitored diagnostic tests are completed, the I/M System Status indicators are set to YES. Perform the Inspection/Maintenance (I/M) Complete System Set Procedure if any I/M System Status indicators are set to NO.

Conditions for Meeting a Cold Start

1. The ignition voltage between 11-18 volts.
2. The barometric pressure (BARO) is more than 75 kPa.
3. The start-up engine coolant temperature (ECT) is between 4-30°C (39-86°F).
4. The start-up intake air temperature (IAT) is between 4-30°C (39-86°F).
5. The difference between the IAT and the ECT is 6°C (10.8°F).
6. The ambient air temperature is between 4-30°C (39-86°F).
7. The fuel level is between 15-85 percent.
8. The vehicle has NOT been refueled since the last cold start ignition cycle.

Review the Inspection/Maintenance (I/M) System Status indicators. All I/M System Status indicators should report YES.

Inspection/Maintenance (I/M) System Set Procedure

1. Ensure that the vehicle meets the conditions for a cold start listed above. If the EVAP I/M System Status indicator displays NO, perform the EVAP Service bay test if applicable. If the EVAP Service bay test is NOT available, it may take up to 6 drive cycles, with 17 hours between drive cycles for the EVAP I/M System Status Indicator to transition to YES. The EVAP I/M System Status indicator requires several drive and 17 hour key OFF cycles to complete before the indicator will transition. If the O2S Heater System Status indicator displays NO, ensure that the ignition has been turned OFF for at least 10 hours.
2. Turn OFF all accessories, HVAC system, other electrical loads, including aftermarket/add-on equipment, etc., and open the hood.
3. Set the vehicle parking brake and ensure the vehicle is in park for automatic transmission or neutral for manual transmission.
4. Turn the ignition ON with the engine OFF for 1 minute.
5. Start and idle the engine for 2 minutes and until 65°C (149°F) is achieved.
6. Run the engine for 6.5 minutes within the following conditions: MAF parameter between 4-30 g/s Engine speed steady between 1,000-3,000 RPM
7. Return the engine to idle for 1 minute.
8. Apply and hold brake pedal, and shift to Drive for automatic, or apply clutch pedal for manual and operate the vehicle within the following conditions for 2 minutes: Depress the accelerator pedal until throttle position (TP) sensor angle is more than 2 percent. MAF signal between 15-30 g/s RPM steady between 1,200-2,000 RPM IMPORTANT: Do NOT touch the accelerator pedal until told to do so. A change in TP sensor angle or an increase in engine speed may invalidate this portion of the test.
9. Release the accelerator pedal and shift the vehicle to Park for automatic, or Neutral and release clutch pedal for manual, and allow the engine to idle for 2 minutes.
10. Quickly depress the accelerator pedal until TP sensor angle is more than 8 percent and return to idle. Repeat 3 times.
11. Allow engine to idle for at least 2 minutes. CAUTION: Refer to «Road Test Caution»(/chevrolet/malibu/vi-2006-2008/remont/oem-general-information/#warnings-and-cautions__road-test-caution) .
12. Close the hood, release the parking brake and drive vehicle at 24 km/h (15 mph) or slower for 2 minutes.
13. Continue to drive the vehicle for at least 5.5 miles between 45-112 km/h (28-70 mph) with the vehicle reaching at least 80 km/h (50 mph).
14. Release the accelerator pedal for at least 3 seconds. This will allow the vehicle to enter the decel fuel cut off.
15. Depress the accelerator pedal until the TP sensor angle is between 3-20 percent and maintain for 1 minute.
16. Safely stop the vehicle, with the engine in drive for automatic or neutral with the clutch pedal depressed and parking brake applied for manual. Allow the vehicle to idle for 2 minutes. IMPORTANT: Do NOT disturb the vehicle or turn ON the ignition until told to do so. Disturbing the vehicle may invalidate this portion of the test.
17. Shift the vehicle to park for automatic and neutral for manual. Turn OFF the ignition and exit the vehicle. Do NOT disturb the vehicle for 45 minutes.
18. Observe the Inspection/Maintenance (I/M) System Status with a scan tool. All of the I/M System Status indicators should display YES. If the EVAP I/M System Status indicator displays NO turn OFF the ignition for 17 hours, ensure that the vehicle meets the conditions for a cold start, and repeat steps 13-18 three more times, or until the EVAP I/M System Status indicator transitions to YES. If the indicator continues to display NO, refer to the «Inspection/Maintenance (I/M) System DTC Table»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting__inspectionmaintenance-im-system-dtc-table) to identify the DTCs that did not run.

1. If any of the I/M System Status indicators display NO, refer to the «Inspection/Maintenance (I/M) System DTC Table»(/chevrolet/malibu/vi-2006-2008/remont/testing-diagnostics/#engine-controls-fuel-35l-diagnosis-troubleshooting__inspectionmaintenance-im-system-dtc-table) for the indicator which did not display YES. The I/M System DTC Table identifies the DTCs associated with each I/M System Status Indicator.

Inspection/Maintenance (I/M) System DTC Table

Inspection/Maintenance (I/M) System DTC Table

The evaporative emission (EVAP) Service Bay Test raises the engine coolant temperature (ECT) threshold so that the temperature sensitive EVAP diagnosis tests can run while in service environments. When the EVAP tests are run the service bay test will indicate a pass or will indicate a specific DTC has failed. The EVAP service bay test can be used to verify an existing condition and verify that the EVAP system is OK after a repair is completed.

Conditions for Running the Test

1. The ignition is ON.
2. The battery voltage is between 9-18 volts.
3. The engine coolant temperature (ECT) is less than 70°C (158°F).
4. The fuel level is 15-85 percent of capacity.
5. The vehicle speed is less than 4.8 km/h (3 mph).
6. Stored DTCs have been cleared.

Test Procedure

1. Install a scan tool.
2. With a scan tool, select the service bay test in the special functions menu.
3. Follow the instructions on the scan tool.
4. Check DTCs with a scan tool.
5. Continue with the diagnostic DTC procedure.

See also:
• Diagnostic System Check - Vehicle
• Scan Tool Data List
• Power and Grounding Schematic Icons
• Power and Grounding Connector End Views
• EMISSION HOSE ROUTING DIAGRAM
• Evaporative Emissions Hose Routing Diagram
• Spark Plug Inspection
• Ignition System Specifications
• Torque Converter Diagnosis
• DTC P0171, P0172, P0174, or P0175
• Symptoms - Engine Exhaust
• Symptoms - Engine Cooling
• Symptoms - Engine Mechanical
• Temperature Versus Resistance
• Symptoms - Engine Electrical
• Crankshaft and Bearings Cleaning and Inspection
• Camshaft Position Actuator Cleaning and Inspection
• Camshaft Position Actuator Magnet Cleaning and Inspection
• Engine Mount Inspection
• Instrument Cluster Schematics
• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs
• Scan Tool Data Definitions
• Scan Tool Output Controls
• Diagnostic Repair Verification
• Control Module References
• Strategy Based Diagnosis
• Diagnostic Procedure Instructions
• Battery Inspection/Test
• Engine Cranks Slowly
• Starting System Description and Operation
• Diagnostic Trouble Code (DTC) List - Vehicle
• DTC P0685, P0689, or P0690
• Spark Plug Wire Inspection
• Restricted Exhaust
• Fuel Pressure Relief
• Special Tools
• Fuel System Cleaning
• Road Test Caution
• Fuel System Diagnosis
• Inspection/Maintenance (I/M) System DTC Table