Engine Controls - System & Component Tests - 2.2L: Other Pontiac Sunfire I

AIR INDUCTION SYSTEMS

Note. Manufacturer does not provide testing procedures for many individual systems and components. For fuel system testing not listed, perform related DTC testing procedure. See SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

Note. For location of components, see COMPONENT LOCATIONS .

COMPUTERIZED ENGINE CONTROLS

Note. For location of components, see COMPONENT LOCATIONS .

POWERTRAIN CONTROL MODULE

Note. To identify circuits, see WIRING DIAGRAMS . For connector terminal identification, see CONNECTOR IDENTIFICATION in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article or CONNECTOR IDENTIFICATION in SELF-DIAGNOSTICS - 2.2L CAVALIER - BI-FUEL - CNG/GASOLINE article.

Ground Circuits

1. Using DVOM, check for continuity to ground at PCM ground terminals. See «WIRING DIAGRAMS»(ref-153404-S25048080582003060900000) . Resistance should be less than 5 ohms. If resistance is not less than 5 ohms, repair open or high resistance in ground circuit.
2. Connect negative lead of DVOM to a known-good ground. Backprobe positive lead of voltmeter to each PCM ground terminal. With vehicle running, DVOM should indicate less than one volt. If DVOM reading is greater than one volt, check for open, short to voltage, corrosion or loose connection in ground circuit.

Power Circuits

1. Using DVOM, check for battery voltage between PCM continuous power terminal(s) and ground. See «WIRING DIAGRAMS»(ref-153404-S25048080582003060900000) . If battery voltage is not present, check for open fuse or fusible link. If fuse or fusible link is okay, check for open in circuit between PCM continuous power terminal and power source.
2. Turn ignition switch to RUN position. Using DMM, check for battery voltage between PCM ignition power terminals and ground. If battery voltage is not present, check PCM/IGN fuse (10-amp) on Alero and Grand Am or PCM fuse (10-amp) on Cavalier and Sunfire. If fuse is okay, check for open in circuit between battery and ignition switch, and between ignition switch and PCM ignition power terminal. If circuits are okay, check for defective ignition switch.
3. Connect DVOM between ground and PCM starter (crank) signal terminal. On vehicles with M/T, depress clutch pedal. On vehicles with A/T, place gearshift lever in Park. On all vehicles, turn ignition switch to START position. Battery voltage should be present only when ignition switch is in START position.
4. If voltage is not present, check CRNK fuse (10-amp) or fusible link between ignition switch and PCM starter (crank) signal terminal. If fuse or fusible link is okay, check for open in circuit between ignition switch and PCM starter (crank) signal terminal, or check for defective ignition switch.

SENSORS & SWITCHES

Note. For additional sensor testing specifications, see SENSOR OPERATING RANGE CHARTS - CARS article.

Note. Perform powertrain diagnostic system check prior to testing, and after completing any repairs. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article or DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS (ALTERNATIVE FUELS) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 2.2L CAVALIER - BI-FUEL - CNG/GASOLINE article.

Note. For location of components, see COMPONENT LOCATIONS .

Manufacturer does not provide testing procedures for many individual systems and components. For fuel system testing not listed, perform related DTC testing procedure. See SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

CAMSHAFT POSITION SENSOR

A malfunction in Camshaft Position (CMP) sensor can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

CRANKSHAFT POSITION SENSOR

A malfunction in Crankshaft Position (CKP) sensor can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

ENGINE COOLANT TEMPERATURE SENSOR

A malfunction in Engine Coolant Temperature (ECT) sensor circuit can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

FUEL GAUGE SELECTOR SWITCH/FUEL INDICATOR LIGHT

A fuel gauge selector switch/fuel indicator light circuit can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L CAVALIER - BI-FUEL - CNG/GASOLINE article.

FUEL LEVEL SENSOR

A fuel level sensor circuit can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

FUEL TANK PRESSURE SENSOR

A Fuel Tank Pressure (FTP) sensor circuit can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article or DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L CAVALIER - BI-FUEL - CNG/GASOLINE article.

HEATED OXYGEN SENSOR

A malfunction in a Heated Oxygen Sensor (HO2S) circuit can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

INTAKE AIR TEMPERATURE SENSOR

A malfunction in Intake Air Temperature (IAT) sensor circuit can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

FUEL RAIL PRESSURE SENSOR

A Fuel Rail Pressure (FRP) sensor circuit can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L CAVALIER - BI-FUEL - CNG/GASOLINE article.

FUEL RAIL TEMPERATURE SENSOR

A Fuel Rail Temperature (FRT) sensor circuit can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L CAVALIER - BI-FUEL - CNG/GASOLINE article.

A Fuel Tank Pressure (FTP) sensor circuit can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L CAVALIER - BI-FUEL - CNG/GASOLINE article.

FUEL TANK TEMPERATURE SENSOR

A Fuel Tank Temperature (FTT) sensor circuit can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L CAVALIER - BI-FUEL - CNG/GASOLINE article.

KNOCK SENSOR

A malfunction in Knock Sensor (KS) circuit can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

MANIFOLD ABSOLUTE PRESSURE SENSOR

A malfunction in Manifold Absolute Pressure (MAP) sensor circuit can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

THROTTLE POSITION SENSOR

A malfunction in TP sensor circuit can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

PARK NEUTRAL POSITION SWITCH

See appropriate DIAGNOSIS article in AUTOMATIC TRANSMISSIONS for testing procedures.

VEHICLE SPEED SENSOR

See appropriate DIAGNOSIS article in AUTOMATIC TRANSMISSIONS.

MOTORS, RELAYS & SOLENOIDS

Note. Manufacturer does not provide testing procedures for many individual systems and components. For fuel system testing not listed, perform related DTC testing procedure. See SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

Note. For location of components, see COMPONENT LOCATIONS .

IDLE AIR CONTROL MOTOR

See IDLE CONTROL SYSTEM .

A/C COMPRESSOR CLUTCH RELAY

See appropriate MANUAL or AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING.

FUEL PUMP RELAY

Fuel pump relay is located in underhood fuse/relay block. Manufacturer does not provide testing procedures for many individual systems and components. See FUEL PUMP ELECTRICAL CIRCUIT DIAGNOSIS under FUEL SYSTEMS. For fuel system testing not listed, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

HIGH PRESSURE LOCK-OFF SOLENOID

A malfunctioning High Pressure Lock-Off Solenoid (HPL) solenoid can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L CAVALIER - BI-FUEL - CNG/GASOLINE article.

LOW PRESSURE LOCK-OFF SOLENOID

A malfunctioning Low Pressure Lock-Off Solenoid (LPL) solenoid can set a DTC. For testing procedures and specifications, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L CAVALIER - BI-FUEL - CNG/GASOLINE article.

FUEL SYSTEMS (GASOLINE)

Note. Perform powertrain diagnostic system check prior to testing, and after completing any repairs. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

Note. For location of components, see COMPONENT LOCATIONS . For circuit identification, see WIRING DIAGRAMS .

Manufacturer does not provide testing procedures for many individual systems and components. For fuel system testing not listed, perform related DTC testing procedure. See SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

FUEL SYSTEM PRESSURE RELEASE

1. Disconnect the negative battery cable.
2. Connect Fuel Pressure Gauge (J 34730-1A), or equivalent, to the fuel pressure connection, located on the fuel rail. (Scheme 71)
3. Place the bleed hose of the fuel pressure gauge into an approved gasoline container.
4. Open the valve to bleed the system pressure. The fuel connections are now safe for servicing.
5. Disconnect the fuel pressure gauge from the fuel pressure connection.

Scheme 71

Fuel pump relay is located in underhood fuse/relay block. Manufacturer does not provide testing procedures for many individual systems and components. See FUEL PUMP ELECTRICAL CIRCUIT DIAGNOSIS .

FUEL DELIVERY

Note. Manufacturer does not provide testing procedures for many individual systems and components. See FUEL PUMP ELECTRICAL CIRCUIT DIAGNOSIS .

Fuel Pressure Regulator

Manufacturer does not provide testing procedures for many individual systems and components. See FUEL SYSTEM DIAGNOSIS (GASOLINE) under FUEL SYSTEMS in BASIC DIAGNOSTIC PROCEDURES - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE article.

FUEL SYSTEM CLEANING

1. Remove the fuel tank.
2. Remove the fuel sender assembly.
3. Inspect the fuel sender strainer.
4. Flush the fuel tank with hot water.
5. Pour the water out of the fuel sender assembly opening in the fuel tank. Rock the fuel tank to be sure that the removal of the water from the fuel tank is complete.
6. Allow the tank to dry completely before reassembly.
7. Disconnect the fuel pipes at the engine compartment fuel pipes. See «FUEL LINE QUICK CONNECT FITTINGS»(ref-153402-S13027093362003040400000) in REMOVAL & INSTALLATION - CAVALIER & SUNFIRE article.
8. Clean the fuel pipes by applying air pressure in the opposite direction of the fuel flow.
9. Connect the fuel pipes to the engine compartment fuel pipes.
10. Replace the fuel filter.
11. Install the fuel sender assembly.
12. Install the fuel tank.

FUEL SYSTEMS (CNG)

Manufacturer does not provide testing procedures for many individual systems and components. For sensor and switch testing not listed, perform related DTC testing procedure. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS (ALTERNATIVE FUELS) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 2.2L CAVALIER - BI-FUEL - CNG/GASOLINE article.

Note. For location of components, see COMPONENT LOCATIONS .

Fuel pump relay is located in underhood fuse/relay block. Manufacturer does not provide testing procedures for many individual systems and components. For fuel system testing not listed, perform related DTC testing procedure. See SELF-DIAGNOSTICS - 2.2L CAVALIER - BI-FUEL - CNG/GASOLINE article.

FUEL TANK CLEANING (CNG)

Note. Tank cleaning is only necessary when a part such as the High Pressure Lock-Off (HPL) solenoid has failed due to fuel contamination or when excess water accumulation, that may reduce fuel capacity, is suspected within the tank.

1. Perform the Fuel Pressure Relief Procedure. See «FUEL SYSTEM PRESSURE RELEASE (CNG)»(ref-153407-S32263073942003052000000) under FUEL SYSTEMS in BASIC DIAGNOSTIC PROCEDURES - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE article.
2. Perform the Fuel Tank Venting Procedure. See «FUEL TANK VENTING (CNG)»(ref-153402-S00524229582003040400000) under FUELS SYSTEMS (CNG) in REMOVAL & INSTALLATION - CAVALIER & SUNFIRE article.
3. Perform the High Pressure Lock-Off (HPL) solenoid removal procedure leaving the HPL installed into the tank finger-tight. See «HIGH PRESSURE LOCK-OFF SOLENOID»(ref-153402-S04436923592003040400000) under FUEL SYSTEMS (CNG) in REMOVAL & INSTALLATION - CAVALIER & SUNFIRE article.
4. Place the CNG Tank Support Harness (J 44244), or equivalent, on the shop floor.
5. Lower the CNG fuel tank on top of the CNG Tank Support Harness.
6. Place the CNG Tank Support Harness support flap so that the HPL protrudes through the flap.
7. Place the CNG Tank Support Harness straps around the CNG fuel tank placing the end strap over the HPL and around the neck of the CNG fuel tank.
8. Securely fasten the CNG Tank Support Harness straps around the CNG fuel tank. Longer CNG fuel tanks will require the use of all the CNG Tank Support Harness straps.
9. Connect the CNG Tank Support Harness to a suitable lifting device.
10. Slowly raise the CNG fuel tank until the HPL is several inches above the ground ensuring that the HPL does not contact the floor during the lifting process.
11. Place a container underneath the HPL to collect any drained fluids.
12. Remove the HPL, allowing any fluids to drain completely from the CNG fuel tank.
13. Dispose of any collected fluids in a safe and approved manner.
14. Flush the inside of the CNG fuel tank using clean water.
15. Dry the inside of the CNG fuel tank using compressed air.
16. Install the HPL finger-tight.
17. Slowly lower the CNG fuel tank back to the ground ensuring the HPL does not contact the ground.
18. Remove the CNG Tank Support Harness from the CNG fuel tank.
19. Complete the installation of the HPL into the tank and the tank into the vehicle by completing the installation steps as indicated in the High Pressure Lock-Off (HPL) Solenoid Replacement. See «HIGH PRESSURE LOCK-OFF SOLENOID»(ref-153402-S04436923592003040400000) under FUEL SYSTEMS (CNG) in REMOVAL & INSTALLATION - CAVALIER & SUNFIRE article.

IDLE CONTROL SYSTEMS

Note. For idle control system testing not listed, perform related DTC testing procedure. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

Note. Perform appropriate Diagnostic System Check - Engine Controls prior to testing, and after completing any repairs. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article or DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS (ALTERNATIVE FUELS) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 2.2L CAVALIER - BI-FUEL - CNG/GASOLINE article.

IGNITION SYSTEMS

Note. For basic ignition system checks, see BASIC DIAGNOSTIC PROCEDURES - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

Note. For ignition system testing, perform related DTC testing procedure. See appropriate SELF-DIAGNOSTICS article.

Spark Plug Usage

Ensure that the correct spark plug is installed. An incorrect spark plug causes driveability conditions. Refer to Ignition System Specifications for the correct spark plug. See IGNITION SYSTEMS in SERVICE & SPECIFICATIONS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE article. Ensure that the spark plug has the correct heat range. An incorrect heat range causes spark plug fouling (colder plug), pre-ignition, causing spark plug and/or engine damage (hotter plug).

EMISSION SYSTEMS & SUB-SYSTEMS

Note. Manufacturer does not provide testing procedures for many individual systems and components. For emission and subsystem testing not listed, perform related DTC testing procedure. See SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

EXHAUST SYSTEM CHECK

For exhaust system symptom diagnosis, see DIAGNOSTIC STARTING POINT - ENGINE EXHAUST under SYMPTOMS in TROUBLE SHOOTING - NO CODES - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.

FUEL EVAPORATION

Note. Ensure all vacuum line and EVAP system components are not damaged or missing before proceeding.

Cleaning Procedure

1. Raise and support the vehicle.
2. Remove the EVAP canister.
3. Turn OFF the main valve on the EVAP Pressure and Purge Station.
4. Disconnect the hose from the diagnostic station pressure regulator.
5. Using a section of vacuum hose, connect one end onto the diagnostic station pressure regulator.
6. Connect the other end of the vacuum hose to the canister side of the purge pipe.
7. Turn ON the main nitrogen cylinder valve and continue to discharge nitrogen for 15 seconds.
8. If the nitrogen does not dislodge the carbon particles, replace the purge pipe.
9. Return the EVAP pressure/purge diagnostic station to the original condition of the station.
10. Install a new EVAP canister.
11. Lower the vehicle.
12. Install a new EVAP canister purge valve.
13. Return to the published service procedure.

Checking PCV Valve Function

1. Disconnect PCV valve vacuum hose from cylinder head cover. (Scheme 72) Run engine at idle. Place thumb over open end of PCV valve vacuum hose to check for vacuum. If vacuum does not exist, check for obstruction in source vacuum supply. If source vacuum supply is okay, replace PCV valve.
2. Turn ignition switch to OFF position. Remove PCV valve. Shake valve and listen for rattle of check valve inside PCV valve. If a clear rattle is not heard, replace PCV valve.
3. Visually inspect valve for varnish or deposits which may make PCV valve operation sticky or restricted, or cause incomplete seating of valve. Replace as necessary.
4. Engine must be sealed for PCV system to function as designed. If leakage, sludging or dilution of oil is noted and PCV system is functioning properly, check engine for cause and repair as required to ensure PCV system will continue to function properly.
5. An engine operating without any crankcase ventilation can be damaged, so it is important to replace PCV valve and air cleaner breather (if equipped) at regular intervals (at least every 30,000 miles). Check all hoses and clamps for failure or deterioration.

Scheme 72

MISCELLANEOUS CONTROLS

Note. Although some of the controlled devices listed here are not technically engine performance components, they can affect driveability if they malfunction.

Note. Manufacturer does not provide testing procedures for many individual systems and components. For system and component testing not listed, perform related DTC testing procedure. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE article or DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS (ALTERNATIVE FUELS) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 2.2L CAVALIER - BI-FUEL - CNG/GASOLINE article.

A/C COMPRESSOR CLUTCH CONTROLS

Note. For A/C compressor clutch circuit testing, see appropriate MANUAL or AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING.

ELECTRIC COOLING FAN

Note. For electric cooling fan circuit testing, see appropriate ELECTRIC COOLING FANS article in ENGINE COOLING.

TRANSMISSION

Note. For transmission electronic controls testing, see appropriate DIAGNOSIS article in AUTOMATIC TRANSMISSIONS. For component circuit identification, see WIRING DIAGRAMS .

ALERO

See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.

CAVALIER

See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.

GRAND AM

See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.

SUNFIRE

See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.