Engine Controls - System/component Tests 4.6L: Other Lincoln Continental IX

Ground Circuits

1. Using a DVOM, check for continuity to ground at the following PCM connector terminals. (Scheme 59) Resistance should be approximately zero ohms. If resistance is not approximately zero ohms, repair circuit open to ground terminals No. 3, 25, 51, 77 and 103.
2. Touch negative lead of voltmeter to a good ground. With vehicle running, backprobe positive lead of voltmeter to each ground terminal. Voltmeter should indicate less than one volt. If reading is greater than one volt, check for open, corrosion or loose connection on ground lead.

Power Circuits

Turn ignition off. Using a voltmeter, check for battery voltage between ground and PCM terminal No. 55 (KAPWR). Turn ignition switch to START or RUN position. Check for battery voltage between ground and PCM connector terminals No. 71 and 97 (VPWR). If battery voltage is not present, power is not being supplied from EEC power relay. See CIRCUIT TEST B in TESTS W/CODES - EEC-V article.

PCM LOCATIONS

Identifying PCM 104-Pin Connector Terminals. Scheme 59

ENGINE SENSORS & SWITCHES

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

Clutch Pedal Position (CPP) Switch

See CIRCUIT TEST TA in TESTS W/CODES - EEC-V article for testing procedure and specifications.

Engine Coolant Temperature (ECT) Sensor

Sensor uses a 5-volt reference voltage during engine operation. To check ECT signal voltage, backprobe between signal terminal and ground with engine running. To check sensor resistance, disconnected sensor and measure resistance between sensor terminals. For specifications, see ECT SENSOR SPECIFICATIONS table. For additional testing information, see CIRCUIT TEST DA in TESTS W/CODES - EEC-V article.

ECT SENSOR SPECIFICATIONS (1)

Heated Oxygen Sensor (HO2S)

Faults in sensor or circuit should set a Diagnostic Trouble Code (DTC). See QUICK TEST in TESTS W/CODES - EEC-V article. If no diagnostic trouble code has been set, go to step 34) of CIRCUIT TEST H in TESTS W/CODES - EEC-V article to check HO2S heater resistance.

Inertia Fuel Shutoff (IFS) Switch

Ensure ignition is off. Locate IFS switch. See INERTIA FUEL SHUTOFF (IFS) SWITCH LOCATION table. Shake or jar IFS switch to cause switch to open and reset button should pop up. Fuel pump should not operate and car should stall. Push down on reset button. Fuel pump should operate.

INERTIA FUEL SHUTOFF (IFS) SWITCH LOCATION

Intake Air Temperature (IAT) Sensor

Sensor uses a 5-volt reference voltage during engine operation. To check IAT signal voltage, backprobe between signal terminal and ground with engine running. To check sensor resistance, disconnected sensor and measure resistance between sensor terminals. For specifications, see IAT SENSOR SPECIFICATIONS table. For additional testing information, see CIRCUIT TEST DA in TESTS W/CODES - EEC-V article.

IAT SENSOR SPECIFICATIONS (1)

Mass Airflow (MAF) Sensor

Faults in MAF sensor or circuit should set a Diagnostic Trouble Code (DTC). See QUICK TEST in TESTS W/CODES - EEC-V article. If no diagnostic trouble code has been set, go to CIRCUIT TEST DC in TESTS W/CODES - EEC-V article for MAF sensor and circuit testing.

Park/Neutral Position (PNP) Switch

See CIRCUIT TEST TA in TESTS W/CODES - EEC-V article for test procedure.

Throttle Position (TP) Sensor

Ensure none of following conditions exist

1. Binding throttle linkage.
2. TP sensor loose or not seated properly.
3. Throttle plate not fully closed.

Faults in TP sensor or circuit should set a diagnostic trouble code. See QUICK TEST in TESTS W/CODES - EEC-V article. If no diagnostic trouble code has been set, see CIRCUIT TEST DH in TESTS W/CODES - EEC-V article for additional sensor testing and specifications.

Fuel Pump Relay

1. Turn ignition off. Leave fuel pump relay disconnected. Measure resistance between terminals No. 1 or No. 85 and all other terminals. To identify fuel pump relay terminals, refer to numbers molded on relay.
2. One resistance measurement should be 40-120 ohms; all other measurements should be greater than 10,000 ohms. Replace fuel pump relay if resistance is not as specified. If resistance is okay, see CIRCUIT TEST KA in «TESTS W/CODES - EEC-V»(ref-131243) article for additional testing procedures.

Canister Vent (CV) Solenoid

See FUEL EVAPORATION under EMISSION SYSTEMS & SUB-SYSTEMS.

Canister Purge (CANP) Solenoid

See FUEL EVAPORATION under EMISSION SYSTEMS & SUB-SYSTEMS.

EGR Vacuum Regulator (EVR) Solenoid

See EXHAUST GAS RECIRCULATION (EGR) under EMISSION SYSTEMS & SUB-SYSTEMS.

Idle Air Control (IAC) Solenoid Resistance

1. Solenoid is by-pass air type. Ensure ignition is off. Disconnect IAC solenoid harness connector. Measure resistance between IAC solenoid connector terminals. Solenoid has diode and resistance will be infinite if voltmeter is hooked up wrong.
2. Resistance should be 6-13 ohms. If resistance is not 6-13 ohms, replace solenoid. If resistance is 6-13 ohms, IAC solenoid may be okay. See CIRCUIT TEST KE in «TESTS W/CODES - EEC-V»(ref-131243) article for additional testing and specifications.

With Fuel Pressure Gauge

Remove fuel tank cap to release fuel tank pressure. Connect Fuel Pressure Gauge (T80L-9974-B) to pressure relief valve (Schrader valve) located on fuel injection manifold rail. Using a suitable container, release fuel pressure.

Without Fuel Pressure Gauge

If fuel pressure gauge is not available, disconnect Inertia Fuel Shutoff (IFS) switch. For IFS location, see INERTIA FUEL SHUTOFF (IFS) SWITCH LOCATION table under ENGINE SENSORS & SWITCHES. Remove fuel cap to release fuel tank pressure. Crank engine for 15 seconds to release system pressure.

See RELAYS under RELAYS & SOLENOIDS.

1. System Integrity Check Perform the following checks: Visually inspect fuel system (fuel lines, filter, pump, injectors, pressure regulator, etc.). Ensure Inertia Fuel Shutoff (IFS) switch reset button is not in upper (tripped) position. Ensure battery is fully charged and fuel-related fuses are okay. Check fuel tank contents and fuel gauge accuracy. On vehicles with 2 fuel tanks, check both tanks. If any fault is detected, repair as necessary. If system checks are okay, go to next step.
2. Check Fuel Pressure Install fuel pressure gauge. Check and record fuel pressure. For fuel pressure specifications, see «FUEL PRESSURE SPECIFICATIONS»(ref-123324) article. If fuel pressure is as specified, testing is complete. If fuel pressure is not as specified, go to step 52) of CIRCUIT TEST H in «TESTS W/CODES - EEC-V»(ref-131243) article.

FUEL PRESSURE REGULATOR

See CIRCUIT TEST HC in TESTS W/CODES - EEC-V article.

Fuel Injector Resistance

Disconnect injector harness connectors. Using digital ohmmeter, measure resistance between injector terminals. See INDIVIDUAL INJECTOR RESISTANCE table. Replace any injector not within specification.

Fuel Injector Check

Start engine and allow to idle. If engine will not start, crank engine for 10 seconds. Using a stethoscope, listen for clicking sound at each injector. If clicking sound is heard, fuel injector is operating. If clicking sound is not heard, go to step 8) of CIRCUIT TEST HD in TESTS W/CODES - EEC-V article.

INDIVIDUAL INJECTOR RESISTANCE (1)

IDLE AIR CONTROL SOLENOID

Turn ignition off. Disconnect IAC wiring harness connector. Connect DVOM positive lead to VPWR (White/Red wire) terminal of IAC solenoid wiring harness connector. Connect DVOM negative lead to IAC terminal. If resistance is 6-13 ohms, go to next step. If resistance is not 6-13 ohms, replace IAC valve assembly.

IGNITION SYSTEM

Note. Vehicles use Coil On Plug (COP). COP faults should set a DTC. For additional testing, see CIRCUIT TEST JF in TESTS W/CODES - EEC-V article.

Note. For additional information and descriptions, see IGNITION SYSTEMS in THEORY/OPERATION - EEC-V article.

Preliminary Check

Perform following preliminary checks

1. Visually inspect engine compartment to verify vacuum hoses and spark plug wires are properly routed and securely connected.
2. Examine all wiring harnesses and connectors for damage.
3. Ensure all ground connections are clean and tight.
4. Ensure battery is fully charged.
5. All accessories should be off during diagnosis.

EXHAUST CATALYST

1. Disable secondary air injection system. Run engine at 2500 RPM for 2 minutes. Turn ignition off. Disconnect and ground one spark plug wire or disconnect one ignition coil for coil on plug applications.
2. Start engine and run at 1000 RPM. Disconnect IAC valve. Using an infrared temperature probe, measure surface temperature at catalytic converter inlet and outlet. Outlet temperature should be at least 50°F (28°C) greater than inlet temperature. Replace catalytic converter if necessary. Reconnect ignition system, IAC valve and secondary air injection.

SECONDARY AIR INJECTION

Note. On models equipped with Electronic Air Injection System (EAIR), go to step 1) of CIRCUIT TEST HM in TESTS W/CODES - EEC-V article. On models equipped with mechanical secondary air injection system, go to step 40) of CIRCUIT TEST HM in TESTS W/CODES - EEC-V article.

EGR Valve

1. Ensure all vacuum hoses are correctly routed and securely attached. Replace any crimped or broken hoses. Ensure there is less than one in. Hg vacuum to EGR valve at idle with engine at normal operating temperature.
2. Install tachometer. Disconnect Idle Air Control (IAC) wiring harness connector. Remove and plug vacuum hose at EGR valve. Start engine. Idle in Neutral. Note idle speed. Using hand vacuum pump, slowly apply 5-10 in. Hg vacuum to EGR valve. When vacuum is fully applied, engine should do one or more of the following: Engine should stall. Idle speed should drop more than 100 RPM. Idle speed should return to normal when vacuum is released.
3. Service or replace EGR valve if engine does not stall or idle speed does not respond as specified. Reconnect IAC harness connector. Unplug and reconnect vacuum hose at EGR valve.

Turn ignition off. Disconnect EVR solenoid wiring harness connector. Measure resistance across EVR solenoid terminals. If resistance is not 26-40 ohms, replace EVR solenoid. For additional testing, go to CIRCUIT TEST HE in TESTS W/CODES - EEC-V article.

FUEL EVAPORATION

Note. For testing of any evaporative emission system component not found here, see CIRCUIT TEST HW in TESTS W/CODES - EEC-V article.

Turn ignition off. Disconnect CANP solenoid wiring harness connector. Measure resistance between CANP solenoid terminals. If resistance is not as specified, replace CANP solenoid. For additional testing, go to CIRCUIT TEST HW in TESTS W/CODES - EEC-V article.

Purge Flow (PF) Sensor

Turn ignition off. Disconnect PF sensor wiring harness connector. Allow sensor to cool to room temperature. Measure resistance between PFS SIG terminal and VPWR terminal. (Scheme 60) If resistance is not 40-230 ohms, replace PF sensor. If resistance is 40-230 ohms, sensor is okay. If fault is still present, go to CIRCUIT TEST HW in TESTS W/CODES - EEC-V article.

Identifying Purge Flow Sensor Connector Terminals. Scheme 60

Turn ignition off. Disconnect CV solenoid wiring harness connector. Measure resistance between CV solenoid terminals. If resistance is not 45-65 ohms, replace CV solenoid and repeat QUICK TEST. If resistance is 45-65 ohms, solenoid is okay. If fault is still present, go to CIRCUIT TEST HX in TESTS W/CODES - EEC-V article.

EVAP Canister

There are no moving parts in canister. Check for loose, missing, cracked or broken connections and parts. Repair or replace as necessary. There should be no liquid in canister.

POSITIVE CRANKCASE VENTILATION (PCV)

1. Check PCV Valve Remove PCV valve. Shake valve and listen for rattle. If PCV valve rattles when shaken, go to next step. Replace PCV valve if it does not rattle when shaken.
2. Check PCV System Start engine and warm to normal operating temperature. Disconnect hose from remote air cleaner or outlet tube. Place a stiff piece of paper over end of hose. If vacuum from hose does not hold paper in place for one minute, repair clogged or leaking hose as necessary. If vacuum from hose holds paper in place for one minute, PCV system is okay and testing is complete.