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Engine Controls - Trouble Shooting - No Codes - Eec-V Ford Econoline I

Testing & Diagnostics ~4825 words

INTRODUCTION

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 article. Use this article to diagnose driveability problems existing when a hard fault code is not present.

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

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 test procedures 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.

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. See COMPUTER RELEARN PROCEDURES article in the GENERAL INFORMATION section before disconnecting battery.

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 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 Idle, Stalls, Misses, Hesitation Or Surge
  2. Hard Start/Long Crank Or Erratic Start/Erratic Crank
  3. No Start/Normal Crank
  4. Slow Return To Idle
  5. High Idle (Diesels/Runs On)
  6. Low Idle (Stalls On Deceleration)
  7. Backfires
  8. Loss Of Power
  9. Spark Knock
  10. Poor Fuel Economy
  11. Emissions Compliance
  12. Warning Indicator Lights
  13. Improper Automatic Transmission Shift
  14. Tachometer Inoperative
  15. High Oil Consumption
  16. Electric Cooling Fan Does Not Run At Low/& Or High Speed
  17. Electric Cooling Fan Always On
  18. Exhaust Smoke
  19. Fuel Smell
  20. Engine Noise
  21. Climate Control (Lack Of Cooling)
  22. Climate Control (A/C Always On)
  23. A/C Does Not Turn Off During WOT
  24. Sulfur Smell

ROUGH IDLE, STALLS, MISSES, HESITATION OR SURGE

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

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.

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 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), go to TEST HE, step 100) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V 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 lean. If VPWR PID voltage is not 10.5-17.0 volts check charging system. If VPWR PID voltage is 10.5-17.0 volts but not within .5 volt of battery voltage, check VPWR circuit and PWR GND circuits. See WIRING DIAGRAMS article.
  2. If engine idles rough at idle, turn ignition off. Turn ignition on. 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 off and disregard any DTCs that are present at this time. On Natural Gas models, go to TEST HA, step 60) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. On all other models, go to TEST H, step 56) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  3. With transmission in Park or Neutral, if engine stalls, check Idle Air Control (IAC) system. See TEST KE, step 2) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  4. Check secondary ignition system. See TEST JB under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  5. Check fuel delivery system. On TEST HB (natural gas vehicles) or TEST HC (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  6. Check exhaust system for restriction. See TEST HF under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  7. Check PCV system. See TEST HG under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  8. On natural gas vehicles, check injector circuits between Natural Gas (NG) module and injectors. See TEST HA, step 57) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  9. On A/T models, ensure transmission is functioning properly. If engine stalls during transmission engagement, check transmission solenoids. See appropriate article in AUTOMATIC TRANSMISSIONS.
  10. Check EVAP system. On Taurus Flex Fuel, if engine stalls, go to TEST HX, step 95) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. For all other symptoms, go to TEST HX, step 92) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. On all other models, if engine stalls, go to TEXT HX, step 19) in SELF-DIAGNOSTICS - EEC-V article. For all other symptoms, go to TEST HX, step 44) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  11. Check engine mechanical condition. Check compression, camshaft, valve train components, etc.
  12. If engine stalls at idle, runs rough at idle, has a rolling idle or has any symptoms associated with a sticking throttle body, go to TEST HU under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  13. On Continental and Windstar, with A/C on, if there is any idle concerns, go to TEST DS, step 22) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  14. Check for driveline faults. On M/T models, check clutch operation. On all models, check charging system. Check for engine surge with A/C on. Check for engine surge with cruise control on. On models with rolling idle and/or engine stumbles when A/C cycles on, check A/C compressor diode. If no problems are indicated, return to «SYMPTOM DIAGNOSIS»(/ford/econoline/i-1985-2013/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v__symptom-diagnosis) to identify any additional symptoms or go to TEST Z under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article and check for intermittent faults.

Check battery condition and starter current draw.

Perform the following

  1. Check secondary ignition system. See TEST JB under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  2. Check fuel delivery system. See TEST HB (natural gas vehicles) or TEST HC (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  3. Check for restricted exhaust system. See TEST HF under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  4. Check Positive Crankcase Ventilation (PCV) system. See TEST HG under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  5. Check Fuel Evaporation (EVAP) system.
  6. Check intake air system. See TEST HU under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  7. Check starting system.
  8. On F150 Lightning Pickup and Super-Duty Pickup models, check secondary circuits used for high speed fuel pump operation. See TEST KA, step 70) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  9. Check for contaminated Mass Airflow (MAF) sensor. If MAF sensor is okay, return to «SYMPTOM DIAGNOSIS»(/ford/econoline/i-1985-2013/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v__symptom-diagnosis) to identify any additional symptoms or go to TEST Z under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article and check for intermittent faults.

NO START/NORMAL CRANK

Extended 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 SELF-DIAGNOSTICS - EEC-V article.

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

Perform the following

  1. Check ignition and fuel system. On Contour, Cougar and Mystique, go to TEST KA, step 75) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. On all others, go to TEST A under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  2. Check if engine will start at part throttle. If engine starts, Idle Air Control (IAC) system may be defective. Go to TEST KE, step 2) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  3. Check for restricted exhaust system. See TEST HF under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  4. Check engine mechanical condition. Check compression, camshaft, valve train components, etc. If no problems are indicated, return to «SYMPTOM DIAGNOSIS»(/ford/econoline/i-1985-2013/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v__symptom-diagnosis) to identify any additional symptoms or go to TEST Z under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V 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 under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  2. Check air intake air system. See TEST HU under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. If air intake system is okay, return to «SYMPTOM DIAGNOSIS»(/ford/econoline/i-1985-2013/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v__symptom-diagnosis) to identify any additional symptoms or go to TEST Z under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V 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 short to power.

Check for vacuum leaks. Check for carbon build-up 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. Check air intake system. See TEST HU under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. If air intake system is okay, return to «SYMPTOM DIAGNOSIS»(/ford/econoline/i-1985-2013/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v__symptom-diagnosis) to identify any additional symptoms or go to TEST Z under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V 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 may not be functioning properly. See appropriate article in AUTOMATIC TRANSMISSIONS.
  2. If idle is low (with A/C on) on F250 (less than 8500 lbs. GVW), F350 (less than 8500 lbs. GVW), Econoline 5.4L and Econoline 6.8L, check ACCS Parameter Identification (PID) value. See PIN VOLTAGE/PID VALUE CHARTS article. With A/C clutch engaged, ACCS PID value should indicate ON. If PID value indicates OFF, go to TEST KM, step 10) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  3. Check fuel delivery fuel system. See TEST HB (natural gas vehicles) or TEST HC (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  4. Check air intake system. See TEST HU under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  5. Check engine mechanical condition. Check compression, camshaft, valve train components, etc. If mechanical condition is okay, return to «SYMPTOM DIAGNOSIS»(/ford/econoline/i-1985-2013/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v__symptom-diagnosis) to identify any additional symptoms or go to TEST Z under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V 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 under SYSTEM TESTS n SELF-DIAGNOSTICS - EEC-V article.
  2. Check fuel delivery system. See TEST HB (natural gas vehicles) or TEST HC (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  3. Check exhaust system for restriction. See TEST HF under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  4. Check engine mechanical condition. Check compression, camshaft, valve train components, etc. If mechanical condition is okay, return to «SYMPTOM DIAGNOSIS»(/ford/econoline/i-1985-2013/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v__symptom-diagnosis) to identify any additional symptoms or go to TEST Z under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article and check for intermittent faults.

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. Also 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 transmission fluid.

Check the following items

  1. Check the following Parameter Identification (PID) values: DPFEGR, LONGFT 1 and LONGFT 2. See 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), go to TEST HE, step 100) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V 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 lean.
  2. On Econoline 4.6L, Explorer 4.0L SOHC, Mountaineer 4.0L SOHC, Pickup 4.6L and all models with a 5.4L engine, also check IMTVF PID. Using scan tool, select IMTVF PID. Turn ignition on and note PID value. Start engine and raise engine speed to 3000 RPM. Again, note PID value. If either PID value indicates YES, go to TEST HU, step 65) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  3. Check fuel delivery system. See TEST HB (natural gas vehicles) or TEST HC (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  4. Check secondary ignition system. See TEST JB under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  5. Check exhaust system. See TEST HF under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  6. Check engine compression. Check engine mechanical condition. Check intake manifold gasket, camshaft and valves.
  7. On A/T models, ensure transmission is functioning properly. If engine stalls during transmission engagement, check transmission solenoids. See appropriate article in AUTOMATIC TRANSMISSIONS.
  8. Check for binding/dragging brakes.
  9. On Contour, Cougar, Econoline 4.2L, Mustang and Mystique, check if A/C turns off under Wide Open Throttle (WOT) conditions. See «A/C DOES NOT TURN OFF DURING WOT»(/ford/econoline/i-1985-2013/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v) symptom.
  10. On F150 Lightning Pickup and Super-Duty Pickup models, check secondary circuits used for high speed fuel pump operation. See TEST KA, step 70) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  11. On M/T models, check clutch operation. On all models, check charging system. Check customer driving habits (i.e., driving with excessive loads). If no problems are indicated, return to «SYMPTOM DIAGNOSIS»(/ford/econoline/i-1985-2013/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v__symptom-diagnosis) to identify any additional symptoms or go to TEST Z under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V 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, go to ENGINE RUNS HOT symptom.
  2. Check engine mechanical condition. Check compression, camshaft, valve train components, etc.
  3. Check fuel delivery system. See TEST HB (natural gas vehicles) or TEST HC (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  4. Check secondary ignition system. See TEST JB under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  5. Check PCV system. See TEST HB under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  6. On models with Knock Sensor (KS), check KS input to PCM. See TEST DG under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  7. Check intake air system. Check engine oil quality. If no problems are indicated, return to «SYMPTOM DIAGNOSIS»(/ford/econoline/i-1985-2013/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v__symptom-diagnosis) to identify any additional symptoms or go to TEST Z under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article and check for intermittent faults.

POOR FUEL ECONOMY

Note. Fuel consumption will increases during stop-and-go driving, trailer towing, short-run operation, extended winter warm-up periods, etc. 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 transmission fluid level. Check fuel quality and coolant level.

Check the following items

  1. Check the following Parameter Identification (PID) values: DPFEGR, LONGFT 1, LONGFT 2 and VPWR. See 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), go to TEST HE, step 100) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V 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 lean. If VPWR PID voltage is not 10.5-17.0 volts check charging system. If VPWR PID voltage is 10.5-17.0 volts but not within .5 volt of battery voltage, check VPWR circuit and PWR GND circuits. See WIRING DIAGRAMS article.
  2. Check secondary ignition system. See TEST JB under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  3. Check fuel delivery system. See TEST HB (natural gas vehicles) or TEST HC (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  4. Check exhaust system. See TEST HF under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  5. Check PCV system. See TEST HG under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  6. Check engine mechanical condition. Check intake manifold gasket, camshaft and valves.
  7. Check for contaminated Mass Airflow (MAF) sensor.
  8. Ensure engine operates at normal operating temperature.
  9. Ensure transmission operates properly.
  10. Check for dragging brakes.
  11. If no problems are indicated, return to «SYMPTOM DIAGNOSIS»(/ford/econoline/i-1985-2013/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes-eec-v__symptom-diagnosis) to identify any additional symptoms or go to TEST Z under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V 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 product fails an I/M test, it is probable that the engine or catalytic converter temperature was not warm and stabilized prior to the test or the vehicle had idled excessively long prior to the test.

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

Check for vacuum leaks/blockage. Check wiring harness connectors. Ensure proper scheduled maintenance has been performed.

Check the following items

  1. If vehicle failed an EVAP Leak Test or a Purge Flow Test only, check for damaged fuel filler cap. Visually check all EVAP lines/hoses for proper connections, damage or blockage. Check EVAP canister for damage. If no problems are indicated, go to TEST HX, step 44) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  2. Check engine emissions. If HC emissions are excessive, check fuel delivery system. See TEST HB (natural gas vehicles) or TEST HC (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. If fuel delivery system is okay, check secondary ignition system. See TEST JB under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. If ignition system is okay, check PCV system. See TEST HG under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. If PCV system is okay, check engine compression. Check engine mechanical condition. Check intake manifold gasket, camshaft and valves.
  3. If NOx emissions are excessive, check engine mechanical condition (excessive cylinder carbon build-up). If engine mechanical condition is okay, on A/T models, check transmission torque converter operation. On all models, check cooling system. If cooling system is okay, check for causes for engine running lean (vacuum leaks, low fuel pressure, etc.). If no problems are found, check catalytic converter efficiency. See appropriate SYSTEMS & COMPONENT TESTING article.
  4. If CO emissions are excessive, check secondary ignition system. See TEST JB under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. If ignition system is okay, check fuel delivery system. See TEST HB (natural gas vehicles) or TEST HC (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. If fuel system is okay, check PCV system. See TEST HG under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. If PCV system is okay, check exhaust system for restriction. See TEST HF under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. If exhaust system is okay, check engine compression. Check engine mechanical condition. Check intake manifold gasket, camshaft and valves.

Preliminary Check

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

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 Malfunction Indicator Light (MIL) concern, check PTO input to PCM. See TEST FB, step 3) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  2. If MIL is always on when engine is running and no DTCs are present, check MIL circuits. On Continental, Expedition, F150, F250 Light Duty, Mustang, Navigator, Town Car and Windstar, go to appropriate INSTRUMENT PANELS article in ACCESSORIES. On all other models, go to TEST NB under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  3. If Malfunction Indicator Light (MIL) does not come on at all, check MIL circuits. On Continental, Expedition, F150 and F250 Light-Duty Picups, Mustang, Navigator, Town Car and Windstar, go to appropriate INSTRUMENT PANELS article in ACCESSORIES. On all other models, go to TEST NB, step 2) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  4. If Transmission Control Indicator (TCIL) does not come on when engine is running and no DTCs are present, check TCIL circuits. See TEST TB, step 6) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  5. If Transmission Control Indicator (TCIL) does not come at all, check TCIL circuits. On Continental, Mustang and Windstar, go to appropriate INSTRUMENT PANELS article in ACCESSORIES. On all other models, go to TEST TB, step 8) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  6. On Escort and Tracer, if Shift Indicator Light (SIL) is always on or always off, go to TEST KL under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  7. If temperature warning indicator light does not function properly, check cooling system. If engine overheats, check and repair cooling system as necessary. If cooling system operates at normal operating temperature, go to TEST DL, step 40) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.

Check transmission fluid level and condition. Check for transmission leaks. Check wiring harness connectors. Check for vehicle modifications. Check for electronic add-on items. Check for misadjusted shift linkage.

Check the following items

  1. Check transmission mechanical components. See appropriate article in AUTOMATIC TRANSMISSIONS.

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

Check the following items

  1. On models with CTO circuit at PCM pin No. 48, go to TEST JH under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. To determine if CTO circuit is used, go to appropriate PIN VOLTAGE/PID VALUE CHART under PIN VOLTAGE/PID VALUE CHARTS article. Check pin No. 48 under OUTPUTS.
  2. Check instrumentation. See appropriate INSTRUMENT PANELS article in ACCESSORIES for diagnosis and testing.

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

Check the following items

  1. Check PCV system. See TEST HG under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V 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.

Perform the following checks

  1. Engine coolant level.
  2. Cooling fan wiring harness connections.
  3. Coolant leaks.
  4. Water/anti-freeze mixture.
  5. Radiator condition.
  6. Collapsed/restricted radiator hoses.
  7. Radiator pressure cap.
  8. Overflow system.

Check the following items

  1. On Escort, Mustang and Tracer, if cooling fan(s) does not operate at all speeds, go to TEST X, step 40) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  2. On all other models, if cooling fan(s) do not operate at all speeds, go to TEST KF, step 30) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.

Check the following items

  1. 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 cooling fan. If cooling fan runs continuously, proceed as follows.
  2. On Escort, Mustang 4.6L and Tracer, go to TEST X, step 80) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  3. On Mustang 3.8L, go to TEST X, step 82) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  4. On Continental and Windstar, go to TEST KF, step 63) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  5. On all other models, go to TEST KF, step 60) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.

Black Smoke (Rich Mixture)

Perform the following

  1. Check for restricted air cleaner/air intake duct.
  2. Check fuel delivery system. See TEST HB (natural gas vehicles) or TEST HC (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  3. Check secondary ignition system. See TEST JB under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.

Blue Smoke (Burning Oil)

Perform the following

  1. Check PCV system. See TEST HG under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V 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.

White Smoke (Water In Combustion)

  1. Check for cylinder head gasket leaks, intake manifold gasket leaks and cracked engine block.

Check fuel system for leaks.

Perform the following

  1. On Natural Gas vehicles, check fuel delivery system for leaks. See TEST HB, step 16) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  2. Check EVAP system. On Taurus Flex Fuel, go to TEST HX, step 92) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. On all other models, go to TEST HX, step 44) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.

Perform the following

Squeal, Click Or Chirp

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

Rattle

  1. Check for loose components.

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.

Snap

  1. Snap noise may be due to secondary ignition arcing. Perform a visual/audible check of secondary ignition system.

Rap Or Roar

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

Note. For additional A/C system information, see appropriate article in HVAC.

On Mustang, go to TEST X, step 98) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. On Contour, Cougar, Econoline 4.2L, and Mystique, go to TEST KM, step 8) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. On all other models, go to appropriate article in HVACl for diagnosis and repair.

On Mustang, go to TEST X, step 40) under SYSTEM TESTS n SELF-DIAGNOSTICS - EEC-V article. On Contour, Cougar, Econoline 4.2L and Mystique, go to TEST KM, step 20) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article. On all other models, go to appropriate article in AIR CONDITIONING & HEATING for diagnosis and repair.

Check the following items

  1. On all models except Contour, Cougar, Econoline 4.2L, Mustang and Mystique, this symptom cannot be present without another A/C symptom also being present. See appropriate article in HVAC for diagnosis of other A/C symptoms.
  2. If vehicle is a Contour, Cougar, Econoline 4.2L, Mustang or Mystique, perform QUICK TEST. See SELF-DIAGNOSTICS - EEC-V article. If any Diagnostic Trouble Codes (DTCs) are present, perform appropriate system test. If no DTCs are present, on Mustang, go to TEST X, step 130) under SYSTEM TESTS in SELF DIAGNOSTICS - EEC-V article. On Contour, Cougar, Econoline 4.2L and Mystique, go to TEST KM, step 25) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.

SULFUR SMELL

Note. On vehicles with a NEW catalytic converter or vehicles with 5000-10,000 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 the following items

  1. Check fuel delivery system. See TEST HB (natural gas vehicles) or TEST HC (except natural gas vehicles) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.
  2. Check Evaporative Emission (EVAP) system. See TEST HX, step 44) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V 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. If fault code is not present, check for intermittents. See TEST Z under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V article.

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