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Engine Controls - Trouble Shooting - No Codes - Eec-V - Gasoline Lincoln Town Car III

Testing & Diagnostics ~6799 words

INTRODUCTION

Note. This article covers gasoline and flex-fuel vehicles with EEC-V systems only. For Bi-Fuel (CNG and gasoline or LPG and gasoline) vehicles with EEC-V systems, see TROUBLE SHOOTING - NO CODES - EEC-V (BI-FUEL) article.

Note. Some driveability problems may have been corrected by manufacturer with a revised Powertrain Control Module (PCM). Check with manufacturer for latest PCM application.

Before diagnosing symptoms or intermittent faults, perform basic diagnostic procedures in appropriate BASIC DIAGNOSTIC PROCEDURES article and perform QUICK TEST in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. Use this article to diagnose driveability problems existing when a hard fault code is not present.

Symptom checks can direct the technician to malfunctioning component(s) for further diagnosis. A symptom should lead to a specific component or system test and/or adjustment.

Use INTERMITTENT PROBLEM DIAGNOSIS under INTERMITTENTS to locate driveability problems that DO NOT occur when the vehicle is being tested. These test procedures should also be used if a soft (intermittent) trouble code was present, but no problem was found during self-diagnostic testing.

Note. For specific testing procedures, see appropriate SYSTEM & COMPONENT TESTING article. For specifications, see appropriate ON-VEHICLE ADJUSTMENTS or SERVICE & ADJUSTMENT SPECIFICATIONS article.

SYMPTOMS

CAUTIONWhen battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. Before disconnecting battery, see COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION.

SYMPTOM DIAGNOSIS

Symptom checks cannot be used properly unless problem occurs while vehicle is being tested. To reduce diagnostic time, ensure steps in appropriate BASIC DIAGNOSTIC PROCEDURES article and SELF-DIAGNOSTICS - EEC-V (GASOLINE) article were performed before diagnosing a symptom. Symptom checks are listed in order of probability, ease of accomplishment, and accessibility. Symptoms available for diagnosis are as follows

  1. «ROUGH OR ROLLING IDLE, STALLS, MISSES, HESITATION OR SURGE»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__rough-or-rolling-idle-stalls-misses)
  2. «HARD START/LONG CRANK OR ERRATIC START/CRANK»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  3. «NO START/NORMAL CRANK»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__no-startnormal-crank)
  4. «SLOW RETURN TO IDLE»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  5. «FAST IDLE (DIESELS/RUNS ON)»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  6. «LOW IDLE (STALLS ON DECELERATION)»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  7. «BACKFIRES»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  8. «LACK/LOSS OF POWER»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__lackloss-of-power)
  9. «SPARK KNOCK»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  10. «POOR FUEL ECONOMY»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__poor-fuel-economy)
  11. «EMISSIONS COMPLIANCE»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__emissions-compliance)
  12. «WARNING INDICATOR LIGHTS»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__warning-indicator-lights)
  13. «IMPROPER AUTOMATIC TRANSMISSION SHIFT»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  14. «TACHOMETER INOPERATIVE»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  15. «HIGH OIL CONSUMPTION»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  16. «ELECTRIC COOLING FAN DOES NOT RUN AT LOW &/OR HIGH SPEED»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  17. «ELECTRIC COOLING FAN ALWAYS ON»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  18. «HYDRAULIC COOLING FAN DRIVE RUNS AT ONE SPEED»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  19. «EXHAUST SMOKE»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  20. «FUEL ODOR»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  21. «ENGINE NOISE»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  22. «CLIMATE CONTROL (LACK OF COOLING)»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__climate-control-lack-of-cooling)
  23. «CLIMATE CONTROL (A/C ALWAYS ON)»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  24. «A/C DOES NOT TURN OFF DURING WOT»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline)
  25. «SULFUR SMELL»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__sulfur-smell-rotten-egg-smell)

ROUGH OR ROLLING IDLE, STALLS, MISSES, HESITATION OR SURGE

WARNINGOn some models, vehicle may stall if engine is left running during refueling. Advise customer to always turn engine off during refueling to avoid contamination or damage to EVAP system.

Note. The Powertrain Control Module (PCM) is equipped with an over RPM/speed limiting function that will shut off fuel delivery when predetermined engine speed is exceeded.

Preliminary Checks

Check for vacuum leaks. Check air intake duct and air filter. Check ignition wiring. Check fuel quality (octane, winter/summer grade fuel, methanol, etc.). Check wiring harness connector for poor connections.

Symptom Checks

Check the following items

  1. Check the following Parameter Identification (PID) values: DPFEGR, LONGFT 1, LONGFT 2 and VPWR. See appropriate PIN VOLTAGE/PID VALUE CHARTS article. On some models, DPFEGR PID may not be applicable. If DPFEGR PID voltage is not .2-1.3 volt with Key On Engine Off (KOEO), see «TEST HE»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 100) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. If LONGFT 1 or LONGFT 2 PID value is low (-20 percent), concentrate checks in areas that would cause engine to run rich. If LONGFT 1 or LONGFT 2 PID value is high (+20 percent), concentrate checks in areas that would cause engine to run lean. If VPWR PID voltage is not 10.5-17.0 volts check and repair charging system as necessary. See appropriate GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS. If VPWR PID voltage is 10.5-17.0 volts but not within .5 volt of battery voltage, check battery supply circuit to power relay (or CCRM) and VPWR circuit between PCM and power relay or CCRM, and PWR GND circuits. See «WIRING DIAGRAMS»(/lincoln/town-car/iii-1997-2003/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article.
  2. If engine idles rough at idle, turn ignition off. Turn ignition switch to ON position. Using scan tool, select INJxF PIDs from PID/DATA monitor menu. There is one INJxF PID available for each engine cylinder and the "x" indicates the appropriate injector number (1-10). If any PID value indicates YES, an injector fault exists. Turn ignition switch to OFF position and disregard any DTCs that are present at this time. On Natural Gas models, see «TEST HA»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 60) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. On all other models, see «TEST H»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 56) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  3. If engine stalls with A/T in Park or Neutral, check Idle Air Control (IAC) system. See «TEST KE»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 2) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  4. Check secondary ignition system. See «TEST JB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  5. Check fuel delivery system. On Natural Gas models, see «TEST HB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) . On all other models, see «TEST HC»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  6. Check exhaust system for restriction. See «TEST HF»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  7. Check PCV system. See «TEST HG»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  8. On natural gas vehicles, check injector circuits between Natural Gas (NG) module and injectors. See «TEST HA»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 57) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  9. On A/T models, ensure transmission is functioning properly. If engine stalls during transmission engagement, check transmission solenoids. See appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.
  10. Check EVAP Emission system for blockages (engine stalls) or leaks (excessive fuel odor). See «SYSTEM TESTS (EVAPORATIVE EMISSIONS)»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  11. Check engine mechanical condition. Check compression, camshaft, valve train components, etc. and repair as necessary. See appropriate article in ENGINES.
  12. Check air intake system, see «TEST HU»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  13. On Continental, LS and Windstar, with A/C on, if there is any idle concerns, see «TEST DS»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 22) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  14. Check for engine surge with cruise control on. Check for engine surge with A/C on. On models with rolling idle and/or engine stumbles when A/C cycles on, check A/C compressor diode. See appropriate MANUAL or AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING. If no problems are indicated, return to «SYMPTOM DIAGNOSIS»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__symptom-diagnosis) to identify any additional symptoms or check for intermittent faults. See «TEST Z»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.

Check battery condition and starter current draw.

Check the following items

  1. Check secondary ignition system. See «TEST JB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  2. Check fuel delivery system. See «TEST HB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (natural gas vehicles) or «TEST HC»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  3. Check for restricted exhaust system. See «TEST HF»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  4. Check PCV system. See «TEST HG»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  5. Check EVAP Emission system for blockages (engine stalls) or leaks (excessive fuel odor). See «SYSTEM TESTS (EVAPORATIVE EMISSIONS)»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  6. Check air intake system. See «TEST HU»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  7. Check starting system. See appropriate STARTERS article in STARTING & CHARGING SYSTEMS.
  8. On F150 Lightning Pickup (5.4L Supercharged) models, check secondary circuits used for high speed fuel pump operation. See «TEST KA»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 70) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  9. Check for contaminated Mass Airflow (MAF) sensor. If MAF sensor is okay, return to «SYMPTOM DIAGNOSIS»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__symptom-diagnosis) to identify any additional symptoms or see «TEST Z»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article and check for intermittent faults.

NO START/NORMAL CRANK

CAUTIONExtended cranking, due to a no-start condition, can load exhaust system with raw fuel, which can ruin catalytic converter after engine is started.

On models with electric Secondary Air Injection (AIR) system, perform the following procedure after the no-start condition has been repaired

  1. Disconnect AIR solid state relay. Start and run engine until surplus fuel is used, and then reconnect relay. Disconnecting AIR solid state relay may set a Diagnostic Trouble Code (DTC). After repairs are completed, clear DTCs. See «CLEARING CODES»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.

Check Inertia Fuel Shutoff (IFS) switch. Check fuel pressure and quality (octane, winter/summer grade fuel, methanol, etc.). Check add-on alarm/anti-theft devices. Check wiring harness connectors. Check for disconnected or restricted air intake duct. Check fuses and relays.

Check the following items

  1. Check ignition and fuel system. On LS models, see «TEST KB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 85) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. On all other models, see «TEST A»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  2. Check if engine will start and run at part throttle. If engine starts and runs, Idle Air Control (IAC) system may be defective. See «TEST KE»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 2) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  3. Check for restricted exhaust system. See «TEST HF»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  4. Check engine mechanical condition. Check compression, camshaft, valve train components, etc. See appropriate article in ENGINES. If no problems are indicated, return to «SYMPTOM DIAGNOSIS»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__symptom-diagnosis) to identify any additional symptoms or see «TEST Z»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article and check for intermittent faults.

Check for vacuum leaks. Check throttle linkage operation. Check throttle body.

Check the following items

  1. Check PCV system. See «TEST HG»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  2. Check air intake system. See «TEST HU»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. If air intake system is okay, return to «SYMPTOM DIAGNOSIS»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__symptom-diagnosis) to identify any additional symptoms or see «TEST Z»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article and check for intermittent faults.

Note. If engine runs normally after ignition key is turned off, check for damaged ignition switch or IGN RUN circuit for short to power.

Check for vacuum leaks. Check for carbon buildup on throttle plate. Check throttle linkage operation. Check for binding/sticking cruise control linkage. Check for air intake duct leaks. Check for leaking intake manifold gasket.

Check the following items

  1. If engine idles fast at idle, turn ignition off. Turn ignition switch to ON position. Using scan tool, select TP V and TPREL PIDs from PID/DATA monitor menu. Check the following PID values: TP V and TPREL while wiggling TP sensor circuits. At vehicle start, TPREL PID reading will begin at about 1.25 volts and count down to the lowest TP V value since engine start-up. If TP V value goes below normal range, then increases again, TPREL will set to lower voltage. If TP V is about .04 volts greater than TPREL value at closed throttle, PCM will go into part throttle mode. Check for loose or worn throttle plates. If no concern is found, see «TEST Z»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article and check for intermittent faults.
  2. Check air intake system. See «TEST HU»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. If air intake system is okay, return to «SYMPTOM DIAGNOSIS»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__symptom-diagnosis) to identify any additional symptoms or see «TEST Z»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article and check for intermittent faults.

Check Idle Air Control (IAC) wiring harness connector. Check for vacuum leaks. Ensure vacuum hoses are routed properly. Check air intake duct.

Check the following items

  1. On A/T models, Torque Converter Clutch (TCC), TCC solenoid or TCC circuit may not be functioning properly. See appropriate OVERHAUL or ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.
  2. For low idle with A/C on, (Econoline 4.6L, 5.4L and 6.8L), check ACCS PID value. See appropriate PIN VOLTAGE/PID VALUE CHARTS article. With A/C clutch engaged, ACCS PID value should indicate ON. If PID value indicates OFF, see «TEST KM»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 10) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  3. Check fuel delivery fuel system. See «TEST HB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (natural gas vehicles) or «TEST HC»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  4. Check air intake system. See «TEST HU»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  5. Check engine mechanical condition. Check compression, camshaft, valve train components, etc. and repair as necessary. See appropriate article in ENGINES. If mechanical condition is okay, return to «SYMPTOM DIAGNOSIS»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__symptom-diagnosis) to identify any additional symptoms or see «TEST Z»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article and check for intermittent faults.

Check vacuum hose routing. Check spark plug wiring (if equipped) for incorrect firing order.

Check the following items

  1. Check secondary ignition system. See «TEST JB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS n SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  2. Check fuel delivery system. See «TEST HB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (natural gas models) or «TEST HC»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (except natural gas models) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  3. Check exhaust system for restriction. See «TEST HF»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  4. Check engine mechanical condition. Check compression, camshaft, valve train components, etc. and repair as necessary. See appropriate article in ENGINES. If mechanical condition is okay, return to «SYMPTOM DIAGNOSIS»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__symptom-diagnosis) to identify any additional symptoms or see «TEST Z»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article and check for intermittent faults.

LACK/LOSS OF POWER

Note. The PCM is equipped with an over RPM/speed limit function. If programmed speed is exceeded, fuel delivery will shut off and DTC P1270 will be set in PCM memory. If vehicle is equipped with a Knock Sensor (KS), a lack of power may result when vehicle is operated with a breakout box installed at PCM. KS circuits are not shielded in the breakout box, and KS signal noise may be noticed by the PCM. If this happens, spark timing will be retarded and a lack of power may result.

Verify symptom is reported under normal driving conditions without engine under excessive load conditions. Check vacuum hose routing. Check for restricted air filter. Check wiring harness connectors. Check throttle linkage. Check for obstructed radiator. Check Automatic Transmission Fluid (ATF) level.

Check the following items

  1. Check the following PID values: DPFEGR, LONGFT 1 and LONGFT 2. See appropriate PIN VOLTAGE/PID VALUE CHARTS article. On some models DPFEGR PID may not be applicable. If DPFEGR PID value is not within .15 volt of Key On Engine Off (KOEO) value, see «TEST HE»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 100) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. If LONGFT 1 or LONGFT 2 PID value is low (-20 percent), concentrate checks in areas that would cause engine to run rich. If LONGFT 1 or LONGFT 2 PID value is high (+20 percent), concentrate checks in areas that would cause engine to run lean.
  2. On Econoline 4.6L, Pickup 4.6L and Navigator 5.4L (4V) engine, also check IMTVF PID. Using scan tool, select IMTVF PID. Ensure transmission is in Park or Neutral. Note PID value when ignition switch is turned to OFF position and then in ON position. Start engine and raise engine speed to 3000 RPM. PID value should indicate NO in both situations. If either PID value indicates YES, see «TEST HU»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 65) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  3. Check fuel delivery system. See «TEST HB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (natural gas models) or «TEST HC»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  4. Check secondary ignition system. See «TEST JB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  5. Check exhaust system. See «TEST HF»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  6. Check engine compression. Check engine mechanical condition and repair as necessary. Check intake manifold gasket, camshaft and valves. See appropriate article in ENGINES.
  7. On A/T models, if engine stalls during transaxle/transmission engagement, check A/T Torque Converter Clutch (TCC) solenoid or circuits. See appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.
  8. Check for binding or dragging brakes. See appropriate article in BRAKES.
  9. On Mustang models, ensure A/C turns off under Wide Open Throttle (WOT) conditions. See «A/C DOES NOT TURN OFF DURING WOT»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline) symptom.
  10. On F150 Lightning Pickup (5.4L Supercharged) models, check supercharger bypass system operation. See «TEST KJ»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. Also on F150 Lightning Pickup (5.4L Supercharged) models, check secondary circuits used for high speed fuel pump operation. See «TEST KA»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 70) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  11. On M/T models, check clutch operation. On all models, check charging system. Check operation of Intake Manifold Runner Control (IMRC) or Intake Manifold Tuning Valve (IMTV), if equipped. Check customer driving habits (i.e., driving with excessive loads). If no problems are indicated, return to «SYMPTOM DIAGNOSIS»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__symptom-diagnosis) to identify any additional symptoms or see «TEST Z»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article and check for intermittent faults.

Check vacuum hose routing. Check for restricted air intake system. Check fuel quality.

Check the following items

  1. Check cooling system for overheating. If cooling system is overheating, repair as necessary. See appropriate article in ENGINE COOLING.
  2. Check Mass Air Flow (MAF) sensor input to PCM. See «TEST DC»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 25) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  3. Check engine mechanical condition. Check compression, camshaft, valve train components, etc. and repair as necessary. See appropriate article in ENGINES.
  4. Check fuel delivery system. See «TEST HB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (natural gas vehicles) or «TEST HC»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  5. Check secondary ignition system. See «TEST JB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  6. Check PCV system. See «TEST HG»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  7. On models with Knock Sensor (KS), check KS input to PCM. See «TEST DG»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  8. Check air intake system. Check engine oil quality. If no problems are indicated, return to «SYMPTOM DIAGNOSIS»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__symptom-diagnosis) to identify any additional symptoms or see «TEST Z»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article and check for intermittent faults.

POOR FUEL ECONOMY

Note. Fuel consumption can be increased during stop-and-go driving, trailer towing, short-run operation, extended winter warm-up periods, improper tire inflation, high speed driving, improper axle ratio and aftermarket add-ons. Determine if these factors are the cause of poor fuel mileage before proceeding with diagnostic procedure.

Check for restricted air filter/air intake duct. Check Automatic Transmission Fluid (ATF) level. Check fuel quality and coolant level.

Check the following items

  1. Check the following PID values: DPFEGR, LONGFT 1, LONGFT 2 and VPWR. See appropriate PIN VOLTAGE/PID VALUE CHARTS article. On some models, DPFEGR PID may not be applicable. If DPFEGR PID value is not within .15 volt of Key On Engine Off (KOEO) value, see «TEST HE»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 100) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. If LONGFT 1 or LONGFT 2 PID value is low (-20 percent), concentrate checks in areas that would cause engine to run rich. If LONGFT 1 or LONGFT 2 PID value is high (+20 percent), concentrate checks in areas that would cause engine to run lean. If VPWR PID voltage is not 10.5-17.0 volts, check charging system. See appropriate GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS. If VPWR PID voltage is 10.5-17.0 volts but not within .5 volt of battery voltage, check battery supply to power relay (or CCRM) and VPWR circuit between PCM and power relay or CCRM, and PWR GND circuits. See «WIRING DIAGRAMS»(/lincoln/town-car/iii-1997-2003/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article.
  2. Check secondary ignition system. See «TEST JB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  3. Check fuel delivery system. See «TEST HB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (natural gas vehicles) or «TEST HC»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  4. Check exhaust system. See «TEST HF»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  5. Check A/T Torque Converter Clutch (TCC) and/or TCC solenoid for proper operation. See appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.
  6. Check PCV system. See «TEST HG»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  7. Check for dragging brakes.
  8. Check engine mechanical condition. Check intake manifold gasket, camshaft and valves and repair as necessary. See appropriate article in ENGINES.
  9. Ensure engine operates at normal operating temperature. Check for contaminated Mass Airflow (MAF) sensor. Check air intake system. If no problems are indicated, return to «SYMPTOM DIAGNOSIS»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__symptom-diagnosis) to identify any additional symptoms or see «TEST Z»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article and check for intermittent faults.

EMISSIONS COMPLIANCE

Canada and some states or metropolitan areas in the United States require periodic emission, or Inspection/Maintenance (I/M) tests. All Ford products have been designed to pass these tests. If a Ford vehicle fails an I/M test, ensure correct model, year, test weight (less than vehicle's GVW) and correct calibration (California or Federal) are on the test report.

Identify which gas readings are high or low and identify in which mode the gas(es) failed. If all gases were high at the beginning of the test then decreased, the engine or catalytic converter temperature may not have been at operating temperature and stabilized prior to the test, or the vehicle had idled for an excessive period of time prior to the test. Perform DIAGNOSTIC ROUTINES after analyzing I/M test report.

If any emission component is changed, Keep-Alive Memory (KAM) should be cleared and basic adaptive strategy should be performed before repeating state emission test procedure. To clear KAM and perform basic adaptive strategy, see RESETTING KEEP-ALIVE MEMORY (KAM) under CLEARING CODES in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.

Diagnostic Routines

  1. 1) Vehicle Failed EVAP Compliance If vehicle failed an EVAP Emissions System Leak Test or a Purge Flow Test only, go to step 35) . If vehicle failed EVAP, Purge Flow and gas tests, go to next step.
  2. 2) Baseline Vehicle Using an exhaust gas analyzer, baseline the vehicle. If vehicle must be driven to achieve baseline, ensure baseline drive cycle is able to be repeated to verify the repairs. During baseline, check for any related symptoms that may be present (driveability, A/T shifting or exhaust smoke). If other symptoms are present, perform «QUICK TEST»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. If no other symptoms are present, go to next step.
  3. 3) Preliminary Checks Check for vacuum leaks or blockage. Check wiring harness connectors. Ensure proper scheduled maintenance has been performed. Check intake air tube and air cleaner for obstructions, leaks or dirty element. Ensure proper emission controls and components are installed on vehicle. Repair as necessary, then go to step 40) . If no repairs are necessary and all checks are okay, go to next step.
  4. 4) Perform PCM Quick Test Perform «QUICK TEST»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article to retrieve Diagnostic Trouble Codes (DTCs). If no DTCs are present, go to next step. If DTCs are present, repair as necessary, then go to step 40) .
  5. 5) Check Carbon Monoxide (CO) Levels Check vehicle CO levels. If vehicle did not have excessive CO levels, go to next step. If vehicle had excessive CO levels, this indicates that engine is running rich. Go to step 15) .
  6. 6) Check Hydrocarbon (HC) Levels Check vehicle HC levels. If vehicle did not have excessive HC levels, go to next step. If vehicle had excessive HC levels with low to normal CO levels, this indicates that engine is running lean. Go to step 25) .
  7. 7) Check Oxides Of Nitrogen (NOx) Levels Check vehicle NOx levels. If vehicle did not have excessive NOx levels, verify all previous testing. If vehicle had excessive NOx levels, go to step 30) .
  8. 15) High CO Levels: Check HC Levels Check vehicle HC levels. If vehicle had excessive HC levels, check for incomplete combustion/running rich. Go to next step. If vehicle did not have excessive HC levels, go to step 17) .
  9. 16) Check Secondary Ignition System See «TEST JB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. Follow diagnostic procedures and repair as necessary, then go to step 40) . If secondary ignition system is okay, go to next step.
  10. 17) Check Fuel Delivery System For Leak-Down Or High Fuel Pressure See «TEST HB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (natural gas models) or «TEST HC»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (except natural gas models) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. Follow diagnostic procedures and repair as necessary, then go to step 40) . If fuel delivery system is okay, go to next step.
  11. 18) Check PCV System See «TEST HG»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. Follow diagnostic procedures and repair as necessary, then go to step 40) . If PCV system is okay, go to next step.
  12. 19) Check Exhaust System See «TEST HF»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. Follow diagnostic procedures and repair as necessary, then go to step 40) . If exhaust system is okay, go to next step.
  13. 20) Check Engine Mechanical Condition See appropriate article in ENGINES. Check compression, camshaft, valve train components, etc., repair as necessary, then go to step 40) . If no engine mechanical problems are indicated and all checks are okay, go to step 45) .
  14. 25) High HC With Normal To Low CO Level, Check Fuel Delivery System Check fuel delivery system for leak-down or low pressure. See «TEST HB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (natural gas models) or «TEST HC»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (except natural gas models) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. Follow diagnostic procedures and repair as necessary, then go to step 40) . If fuel delivery system is okay, go to next step.
  15. 26) Check Secondary Ignition System See «TEST JB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. Follow diagnostic procedures and repair as necessary, then go to step 40) . If secondary ignition system is okay, go to next step.
  16. 27) Check PCV System See «TEST HG»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. Follow diagnostic procedures and repair as necessary, then go to step 40) . If PCV system is okay, go to next step.
  17. 28) Check Engine Mechanical Condition See appropriate article in ENGINES. Check compression, camshaft, valve train components, etc., repair as necessary, then go to step 40) . If no engine mechanical problems are indicated and all checks are okay, go to step 45) .
  18. 30) High NOx With Normal To Low HC & CO Levels Check engine for concerns such as excessive carbon build-up in combustion chamber, repair as necessary, then go to step 40) . See appropriate article in ENGINES. If no engine mechanical problems are indicated, check A/T Torque Converter Clutch (TCC) operation and cooling system. Check for running lean concerns (vacuum leaks or low fuel pressure), go to step 25) . Repair as necessary. If all checks are okay, go to step 45) .
  19. 35) EVAP System Concern: Preliminary Checks Check I/M test report to determine when concern is present. Verify concern and inspect and repair the following as necessary: Check fuel filler cap for proper installation, physical damage or contamination. Check EVAP system hoses and lines for proper connection, damage or blockage. Check fuel vapor storage canister for damage. If all checks are okay, go to next step. If repairs have been performed, go to step 38) .
  20. 36) Perform PCM Quick Test Perform «QUICK TEST»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article to retrieve Diagnostic Trouble Codes (DTCs). If no DTCs are present, go to next step. If DTCs are present, repair as necessary, then go to step 38) .
  21. 37) Check EVAP Emissions System For Leaks See appropriate symptom in «SYSTEM TESTS (EVAPORATIVE EMISSIONS)»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. Follow diagnostic procedures and repair as necessary, then go to step 38) . If EVAP Emission system is okay, verify test results. If results are okay, go to «TEST Z»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. Follow diagnostic procedures and repair as necessary, then go to step 38) .
  22. 38) EVAP Emissions System Repair Verification After making repairs to EVAP emissions system, reset KAM and relearn basic adaptive strategy. See «RESETTING KEEP-ALIVE MEMORY (KAM)»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under CLEARING CODES in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. Repeat PCM QUICK TEST. See «QUICK TEST»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. Repair any DTCs that may be retrieved and perform EVAP system leak test and flow check. See «SYSTEM TESTS (EVAPORATIVE EMISSIONS)»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. If original concern has not been corrected or if another concern exists, repeat step 1) .
  23. 40) Repair Verification After making repairs to appropriate system, reset KAM and relearn basic adaptive strategy. See «RESETTING KEEP-ALIVE MEMORY (KAM)»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under CLEARING CODES in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. Repeat PCM QUICK TEST. See «QUICK TEST»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. Repair any DTCs that may be retrieved and perform baseline test using gas analyzer. If vehicle requires driving for the baseline test, drive at least 5 miles to relearn some additional Adaptive Learning Strategy (trim values). If a gas level is still high or another gas level is above acceptable range, repeat step 1) .
  24. 45) Catalyst Delta Temperature Test Disconnect connector or hoses from secondary AIR system, if equipped. Start and run engine for 2 minutes at 2500 RPM to heat exhaust system. Turn ignition switch to OFF position. Disconnect and ground one spark plug wire from each cylinder bank (for COP applications, disconnect one coil connector from each cylinder bank). Start and run engine at 1000 RPM. Disconnect Idle Air Control (IAC) valve while maintaining 1000 RPM. Using an infrared temperature probe, measure temperature at both the inlet and outlet of each catalytic converter. If the temperature difference between inlet and outlet of each catalytic converter is 50°F (28°C) or less, repeat test step to verify readings. If temperature differences are still 50°F (28°C) or less, replace affected catalytic converter. Reconnect all connectors, IAC valve and AIR system. Go to step 40) . If the temperature difference between inlet and outlet of each catalytic converter is more than 50°F (28°C), the catalytic converters are operating correctly. Reconnect all connectors, IAC valve and AIR system. Repeat PCM QUICK TEST and verify test results. See «QUICK TEST»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. If results are okay, go to «TEST Z»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. Follow diagnostic procedures and repair as necessary, then go to step 40) .

WARNING INDICATOR LIGHTS

Note. If exhaust emission test fails and Malfunction Indicator Light (MIL) is on, see EMISSIONS COMPLIANCE symptom. If engine is a no-start, see NO START/NORMAL CRANK symptom. If engine runs rough at idle, see ROUGH OR ROLLING IDLE, STALLS, MISSES, HESITATION OR SURGE symptom.

The following warning indicators may illuminate

  1. Malfunction Indicator Light (MIL)
  2. Transmission Control Indicator Light (TCIL)
  3. Shift Indicator Light (SIL)
  4. Temperature Warning Indicator Light
  5. Check Fuel Cap Indicator Light

Preliminary Check

Check for wiring harness connectors. Ensure fuel filler cap is installed and tightened properly.

Check the following items

  1. On Pickups with Power Takeoff (PTO) and MIL concern, check PTO input to PCM. See «TEST FB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 3) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  2. If MIL is always on when engine is running and no DTCs are present, check MIL circuits. On Continental, Expedition, Focus, F150, LS, Mustang, Navigator, Town Car or Windstar, see appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. On all other models, see «TEST NB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  3. If TCIL is always on when engine is running and no DTCs are present, check TCIL circuits. On Continental, Focus, LS, Mustang, Town Car or Windstar, see appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. On all other models, see «TEST TB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 6) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  4. If Malfunction Indicator Light (MIL) does not come on at all (including bulb check when engine is first started), check MIL circuits. On Continental, Expedition, Focus, F150, LS, Mustang, Navigator, Town Car or Windstar, see appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. On all other models, see «TEST NB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 2) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  5. If Transmission Control Indicator (TCIL) never comes on, check TCIL circuits. On Continental, Focus, LS, Mustang, Town Car or Windstar, see appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. On all other models, see «TEST TB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 8) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  6. If temperature warning indicator light does not function properly, check cooling system or indicator light circuits. If engine overheats, check and repair cooling system as necessary. If cooling system operates at normal operating temperature, see «TEST DL»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 40) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  7. If SIL is always on or always off, check SIL circuits. See «TEST KL»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  8. If fuel cap indicator light is always on and no DTCs are present, check fuel cap indicator light circuits. See «TEST HX»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 88) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  9. If fuel cap indicator light is always off and no DTCs are present, check fuel cap indicator light circuits. See «TEST HX»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 89) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  10. If no problems are indicated, return to «SYMPTOM DIAGNOSIS»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v-gasoline__symptom-diagnosis) to identify any additional symptoms or see «TEST Z»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article and check for intermittent faults.

Check Automatic Transmission Fluid (ATF) level and condition. Check for A/T leaks. Check wiring harness connectors and A/T shift solenoids and Torque Converter Clutch (TCC) solenoid operation. Check for vehicle modifications. Check for electronic add-on items. Check for misadjusted shift linkage.

Check A/T mechanical components. See appropriate OVERHAUL article in AUTOMATIC TRANSMISSIONS. If no problems are indicated, return to SYMPTOM DIAGNOSIS to identify any additional symptoms or see TEST Z under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article and check for intermittent faults.

Check wiring harness connectors for loose, damaged or corroded terminals.

Check the following items

  1. On models with Clean Tach Output (CTO) circuit at PCM pin No. 48, check CTO circuit from PCM. See «TEST JH»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. To determine if CTO circuit is used, see appropriate PIN VOLTAGE/PID VALUE CHARTS article. Check pin No. 48 under OUTPUTS.
  2. Check instrumentation. See appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT.

Check for external engine oil leaks. Check for correct oil dipstick. Check for proper oil viscosity.

Check the following items

  1. Check PCV system. See «TEST HG»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  2. Check engine mechanical condition. Check valves, valve guides, valve stem oil seals, intake manifold gaskets, cylinder head oil drain passages and piston rings. See appropriate article in ENGINES.

Perform the following checks

  1. Engine coolant level.
  2. Electric cooling fan(s) do not operate properly.
  3. Cooling fan wiring harness connections.
  4. Coolant leaks.
  5. Water/anti-freeze mixture.
  6. Radiator condition.
  7. Collapsed/restricted radiator hoses.
  8. Radiator pressure cap.
  9. Overflow system.

Check the following items

  1. On Escort and Mustang, if cooling fan(s) do not operate at all speeds, see «TEST X»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 40) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  2. On all other models, if cooling fan(s) do not operate at all speeds, see «TEST KF»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 30) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.

Ensure all accessories, A/C and defroster are off, and engine is cooled (so cooling fan would not normally come on). Start engine. Check electric or hydraulic cooling fan. If cooling fan runs continuously, perform the following

  1. On Escort 2.0L and Mustang 4.6L, see «TEST X»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 80) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  2. On Mustang 3.8L, see «TEST X»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 82) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  3. On Continental and Windstar, see «TEST KF»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 63) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  4. On all other models, see «TEST KF»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 60) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.

Check the following items

  1. Engine coolant level.
  2. Hydraulic cooling fan drive solenoid damaged.
  3. Hydraulic cooling fan drive wiring harness connections.
  4. Coolant leaks.
  5. Water/anti-freeze mixture.
  6. Radiator condition.
  7. Collapsed/restricted radiator hoses.
  8. Radiator pressure cap.
  9. Degas Bottle damaged.

Check the following; On LS, if hydraulic cooling fan does not operate at all speeds, see HYDRAULIC COOLING FAN article in ENGINE COOLING.

Black Smoke (Rich Mixture)

Check the following items

  1. Check for restricted air cleaner or air intake duct.
  2. Check fuel delivery system. See «TEST HB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (natural gas vehicles) or «TEST HC»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  3. Check secondary ignition system. See «TEST JB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.

Blue Smoke (Burning Oil)

Check the following items

  1. Check PCV system. See «TEST HG»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  2. Check engine mechanical condition. Check valve guides, valve stems, valve seals, oil drain passages in cylinder heads (Blue smoke on start-up), piston rings and cylinder bores and repair as necessary. See appropriate article in ENGINES.

White Smoke (Water In Combustion)

Check for cylinder head gasket leaks, intake manifold gasket leaks and cracked engine block and repair as necessary. See appropriate article in ENGINES.

Check fuel tank(s), hoses, connectors and lines for leaks.

Check the following items

  1. On Natural Gas models, check fuel delivery system for leaks. See «TEST HB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 16) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  2. On all models, check EVAP emission system for leaks. See «SYSTEM TESTS (EVAPORATIVE EMISSIONS)»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.

Hiss

  1. Check for cooling system leaks.
  2. Check for vacuum leaks.
  3. Check for loose spark plugs.
  4. Check for air intake leaks.
  5. Check for secondary air injection leaks.
  6. Check for Evaporative Emission (EVAP) system leaks.

Knock

  1. Check for worn rod/main bearings.
  2. Check for loose piston pins.
  3. Check piston to cylinder bore clearance.
  4. Knock (Detonation) - See SPARK KNOCK symptom.

Rap Or Roar

  1. Check for exhaust leak.
  2. Check for secondary air injection leaks.

Rattle

Check for loose components.

Snap

Snap noise may be due to secondary ignition arcing. Check secondary ignition system. See TEST JB under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.

Squeal, Click Or Chirp

  1. Check for low oil level.
  2. Check valve train components.
  3. Check drive belts.
  4. Check EEC-V solenoids.

CLIMATE CONTROL (LACK OF COOLING)

Note. For additional A/C system information, see appropriate MANUAL or AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING.

Check the following items

  1. On Mustang, see «TEST X»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 98) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  2. On all other models, see appropriate MANUAL or AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING for diagnosis and repair.
  3. If directed here from an air conditioning diagnostics article with Parameter Identification (PID) WACF displaying YES (fault indicated). See «DIAGNOSTIC TROUBLE CODE (DTC) REFERENCE CHARTS»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article for diagnosis and repair for Key On Engine Off (KOEO) DTC P1460.

See TEST X , step 140) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.

Check the following items

  1. On Mustang, see «TEST X»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) , step 130) under SYSTEM TESTS in SELF DIAGNOSTICS - EEC-V (GASOLINE) article.
  2. On all other models, see appropriate MANUAL or AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING for diagnosis and repair.

SULFUR SMELL (ROTTEN EGG SMELL)

Note. On vehicles with a NEW catalytic converter or vehicles with 5,000-10,000 miles, sulfur smell may be normal due to the highly active state of the converter. Replacing the catalytic converter on these vehicles may make the Sulfur smell worse.

Check wiring harness connectors for loose, damaged or corroded terminals. Check vacuum hoses. Verify odor is from exhaust and not from under hood odor, such as battery acid. Check that there are no other driveability or exhaust smoke symptoms. See SYMPTOM DIAGNOSIS under SYMPTOMS.

Check the following items

  1. Check fuel delivery system. See «TEST HB»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (natural gas vehicles) or «TEST HC»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  2. Check EVAP emission system for leaks. See «SYSTEM TESTS (EVAPORATIVE EMISSIONS)»(/lincoln/town-car/iii-1997-2003/remont/testing-diagnostics/#engine-controls-self-diagnostics-eec-v-cng-flex-fuel-gasoline) in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.
  3. Sulfur content can vary in different fuels. Try a different fuel source.

INTERMITTENT PROBLEM DIAGNOSIS

Intermittent fault testing requires duplicating circuit or component failure to identify the problem. These procedures may lead to the PCM setting a fault code, which may help in diagnosis. To reproduce conditions creating an intermittent fault, use the following methods

  1. Lightly vibrate component.
  2. Heat component.
  3. Wiggle or bend wiring harness.
  4. Spray component with water.
  5. Remove/apply vacuum source.

Monitor circuit/component voltage or resistance while simulating intermittent. If engine is running, monitor for self-diagnostic codes. Use test results to identify a faulty component or circuit. If fault code is not present, check for intermittents. See

under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V (GASOLINE) article.

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