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Engine Controls - Trouble Shooting - No Codes - Eec-V - Cng & Gasoline: Diagnosis Ford Focus I

Testing & Diagnostics ~6633 words

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 - CNG & 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»(ref-40665-S35125482442001011200000)
  2. «HARD START/LONG CRANK OR ERRATIC START/CRANK»(ref-40665-S01132287482001011200000)
  3. «NO START/NORMAL CRANK»(ref-40665-S11597365782001011200000)
  4. «SLOW RETURN TO IDLE»(ref-40665-S24622318982001011200000)
  5. «FAST IDLE (DIESELS/RUNS ON)»(ref-40665-S07029421452001011200000)
  6. «LOW IDLE (STALLS ON DECELERATION)»(ref-40665-S42617107452001011200000)
  7. «BACKFIRES»(ref-40665-S15656584162001011200000)
  8. «LACK/LOSS OF POWER»(ref-40665-S23268263442001011200000)
  9. «SPARK KNOCK»(ref-40665-S32305331552001011200000)
  10. «POOR FUEL ECONOMY»(ref-40665-S03929882832001011200000)
  11. «EMISSIONS COMPLIANCE»(ref-40665-S30237001782001011200000)
  12. «HISSING SOUND WHEN REMOVING FUEL CAP»(ref-40665-S15561549922001081500000)
  13. «EXCESSIVE FUEL ODOR»(ref-40665-S42881220732001081500000)
  14. «UNABLE TO REFUEL VEHICLE»(ref-40665-S06787595532001081500000)
  15. «WARNING INDICATOR LIGHTS»(ref-40665-S16751330662001011200000)
  16. «AUTOMATIC TRANSMISSION DOWN OR UPSHIFT, OR ENGAGEMENT»(ref-40665-S05415296682001011200000)
  17. «SPEEDOMETER OR TACHOMETER INOPERATIVE»(ref-40665-S41548242202001011200000)
  18. «HIGH OIL CONSUMPTION»(ref-40665-S13170374832001011200000)
  19. «ELECTRIC COOLING FAN INOPERATIVE AT LOW, MEDIUM &/OR HIGH SPEED, OR HYDRAULIC COOLING FAN INOPERATIVE (LS)»(ref-40665-S25733954432001011200000)
  20. «ELECTRIC OR HYDRAULIC COOLING FAN(S) ALWAYS ON»(ref-40665-S09765118342001011200000)
  21. «EXHAUST SMOKE»(ref-40665-S28170261212001011200000)
  22. «FUEL ODOR»(ref-40665-S18797629612001011200000)
  23. «ENGINE NOISE»(ref-40665-S35460502322001011200000)
  24. «CLIMATE CONTROL (LACK OF COOLING OR A/C INOPERATIVE)»(ref-40665-S00796218562001011200000)
  25. «CLIMATE CONTROL (A/C ALWAYS ON)»(ref-40665-S11933757902001011200000)
  26. «A/C DOES NOT TURN OFF DURING WOT»(ref-40665-S24287622302001011200000)
  27. «EXHAUST ODOR (SULFUR SMELL)»(ref-40665-S07365834052001011200000)

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 HOT IDLE PID value is not within .15 volt of KOEO value, go to TEST HE, step 100) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & 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 value 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 B+ circuit to power relay (or CCRM), VPWR circuit between PCM and power relay or CCRM, and PWR GND circuits. See WIRING DIAGRAMS article.
  2. If engine runs rough at idle, turn ignition switch to OFF position. Turn ignition switch to ON position. Using scan tool, select INJxF PIDs from PID/DATA MONITOR & RECORD menu. There is one INJxF PID available for each engine cylinder and the "x" indicates the appropriate injector number (1-10). If any INJxF 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, go to TEST HA, step 60) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. On all other models, go to TEST H, step 56) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  3. If engine stalls with A/T in Park or Neutral, check Idle Air Control (IAC) system. Go to TEST KE, step 2) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  4. Check Mass Air Flow (MAF) sensor. Go to TEST DC, step 25) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  5. Check secondary ignition system. Go to TEST JB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  6. Check fuel delivery system. On Natural Gas models, go to TEST HB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. On all other models, go to TEST HC, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  7. Check exhaust system for restriction. Go to TEST HF, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  8. Check PCV system. Go to TEST HG, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  9. On natural gas vehicles with rough idle, check injector circuits between Natural Gas (NG) module and injectors. Go to TEST HA, step 57) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  10. Check EVAP emission system for blockages (engine stalls) or leaks (excessive fuel odor). Service appropriate symptom under SYSTEM TESTS (EVAPORATIVE EMISSIONS) in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  11. 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.
  12. Check engine mechanical condition. Check compression, camshaft, valve train components, etc. and repair as necessary. See appropriate article in ENGINES.
  13. Check air intake system, go to TEST HU, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  14. On Continental, LS and Windstar, for idle concerns with A/C on, go to TEST DS, step 22) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  15. For additional intermittent testing, go to TEST Z, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  16. Ensure Powertrain Control Module (PCM) Vehicle Identification (VID) block is correct. Check engine RPM/speed limiting functions of PCM (proper high vehicle speed signal from ABS, VSS or OSS). Check cruise control system if engine surges with cruise control on. See appropriate CRUISE CONTROL SYSTEMS article in ACCESSORIES & EQUIPMENT. If engine surges with A/C on, or has a rolling idle and/or engine stumble when A/C cycles on, check A/C system and A/C compressor diode. See appropriate MANUAL or AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING.

Check the following items

  1. Check secondary ignition system. Go to TEST JB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  2. Check fuel delivery system. On Natural Gas models, go to TEST HB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. On all other models, go to TEST HC, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  3. Check exhaust system for restriction. Go to TEST HF, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  4. Check PCV system. Go to TEST HG, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  5. Check EVAP emission system for blockages (engine stalls) or leaks (excessive fuel odor). Service appropriate symptom under SYSTEM TESTS (EVAPORATIVE EMISSIONS) in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  6. Check air intake system. Go to TEST HU, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  7. Check starting system. See appropriate STARTERS article in STARTING & CHARGING SYSTEMS.
  8. Check for contaminated Mass Airflow (MAF) sensor. If MAF sensor is okay, return to «SYMPTOM DIAGNOSIS»(ref-40665-S19133719652001011200000) to identify any additional symptoms or go to TEST Z under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article and check for intermittent faults.
  9. On F150 Lightning Pickup (5.4L Supercharged) models, check high speed fuel pump secondary circuits. Go to TEST KA, step 70) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.

Check the following items

  1. Check fuel and ignition systems. On LS models, go to TEST KB, step 85) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. On all other models, go to TEST A, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  2. Check if engine will start and run normally at part throttle. If engine starts and runs only at part throttle, Idle Air Control (IAC) system may be defective. Go to TEST KE, step 2) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  3. Check exhaust system for restriction. Go to TEST HF, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  4. Check engine mechanical condition. Check compression, camshaft, valve train components, etc. See appropriate article in ENGINES. If no problems are indicated, go to TEST Z, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article and check for intermittent faults.

Check the following items

  1. Check PCV system. Go to TEST HG, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  2. Check air intake system. Go to TEST HU, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. If air intake system is okay, go to TEST Z, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article and check for intermittent faults.

Check the following items

  1. For fast idle concern, turn ignition switch to OFF position. Turn ignition switch to ON position. Using scan tool, select TP V and TPREL PIDs from PID/DATA MONITOR & RECORD menu. Observe TP V and TPREL PIDs while wiggling TP sensor circuits. At vehicle start, TPREL PID value will begin at about 1.25 volts and count down to the lowest TP V value read since engine start-up. If TP V value goes below normal range, then increases again, TPREL will set to the lower voltage. If TP V is about .04 volt more 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, go to TEST Z, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article and check for intermittent faults.
  2. Check air intake system. Go to TEST HU, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. If air intake system is okay, go to TEST Z, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article and check for intermittent faults.

Check the following items

  1. On A/T models that stall or quit on deceleration, 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 PIN VOLTAGE/PID VALUE CHARTS - TRUCKS article. With A/C clutch engaged, ACCS PID value should indicate ON. If ACCS PID value indicates OFF, go to TEST KM, step 10) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  3. Check fuel delivery system. On Natural Gas models, go to TEST HB, step 1) . On all other models, go to TEST HC, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  4. Check air intake system. Go to TEST HU, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  5. Check engine mechanical condition. Check compression, camshaft, valve train components, etc. and repair as necessary. See appropriate article in ENGINES. If engine mechanical condition is okay, check fuel filler cap for damage or improper installation. Repair as necessary. If fuel filler cap is okay, go to TEST Z, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article and check for intermittent faults.

Check the following items

  1. Check secondary ignition system. Go to TEST JB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  2. Check fuel delivery system. On Natural Gas models, go to TEST HB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. On all other models, go to TEST HC, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & 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 exhaust system for restriction. Go to TEST HF, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. If exhaust system is okay, go to TEST Z, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article and check for intermittent faults.

Check the following items

  1. Check DPFEGR, LONGFT 1 and LONGFT 2 PID values. See appropriate PIN VOLTAGE/PID VALUE CHARTS article. On some models DPFEGR PID may not be applicable. If DPFEGR HOT IDLE PID value is not within .15 volt of KOEO value, go to TEST HE, step 100) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & 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 and 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. Record IMTVF PID value when ignition switch is turned to OFF position. Then start engine and raise engine speed to 3000 RPM. IMTVF PID value should indicate NO in both situations. If IMTVF PID value indicates YES during either situation, go to TEST HU, step 65) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  3. Check fuel delivery system. On Natural Gas models, go to TEST HB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. On all other models, go to TEST HC, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  4. Check secondary ignition system. Go to TEST JB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  5. Check Mass Air Flow (MAF) sensor. Go to TEST DC, step 25) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  6. Check exhaust system for restriction. Go to TEST HF, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  7. Check engine compression. Check engine mechanical condition and repair as necessary. Check intake manifold gasket, camshaft and valves. See appropriate article in ENGINES.
  8. On A/T models, diagnose by symptom (POOR PERFORMANCE). See appropriate OVERHAUL or ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.
  9. Check for binding or dragging brakes. See appropriate article in BRAKES.
  10. On Mustang models, ensure A/C turns off under Wide Open Throttle (WOT) conditions. See «A/C DOES NOT TURN OFF DURING WOT»(ref-40665-S24287622302001011200000) symptom.
  11. On F150 Lightning Pickup (5.4L SC) models, check supercharger bypass system operation. Go to TEST KJ, step 13) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. Also on F150 Lightning Pickup (5.4L SC) models, check high speed fuel pump secondary circuits. Go to TEST KA, step 70) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  12. Ensure Powertrain Control Module (PCM) Vehicle Identification (VID) block is correct. Check engine RPM/speed limiting functions of PCM (proper high vehicle speed signal from ABS, VSS or OSS). 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, go to TEST Z, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article and check for intermittent faults.

Check the following items

  1. Ensure engine is not exceeding normal operating temperature. Check cooling system for overheating, correct coolant level and coolant concentration. If cooling system is overheating, repair as necessary. See appropriate article in ENGINE COOLING.
  2. Check Mass Air Flow (MAF) sensor input to PCM. Go to TEST DC, step 25) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  3. Check engine mechanical condition. Check compression, camshaft, valve train components, etc. and repair as necessary. Check engine oil quality. See appropriate article in ENGINES.
  4. Check fuel delivery system. On Natural Gas models, go to TEST HB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. On all other models, go to TEST HC, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  5. Check secondary ignition system. Go to TEST JB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  6. Check PCV system. Go to TEST HG, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  7. On models with Knock Sensor (KS), check KS input to PCM. Go to TEST DG, step 15) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  8. For additional testing, go to TEST Z, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article and check for intermittent faults.

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 HOT IDLE PID value is not within .15 volt of KOEO value, go to TEST HE, step 100) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & 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 value 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 B+ circuit to power relay (or CCRM), VPWR circuit between PCM and power relay or CCRM, and PWR GND circuits. See WIRING DIAGRAMS article.
  2. Ensure engine is operating at normal operating temperature. Check cooling system for stuck open or closed thermostat, correct coolant level or coolant concentration. Repair as necessary. See appropriate article in ENGINE COOLING.
  3. Check secondary ignition system. Go to TEST JB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  4. Check fuel delivery system. On Natural Gas models, go to TEST HB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. On all other models, go to TEST HC, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  5. Check exhaust system for restriction. Go to TEST HF, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  6. 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.
  7. Check PCV system. Go to TEST HG, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  8. Check for binding or dragging brakes. See appropriate article in BRAKES. Ensure Powertrain Control Module (PCM) Vehicle Identification (VID) block is correct. Check engine mechanical condition. Check intake manifold gasket, camshaft and valves and repair as necessary. See appropriate article in ENGINES. Check for contaminated Mass Airflow (MAF) sensor. Check air intake system. If no problems are indicated, go to TEST Z, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article and check for intermittent faults.

Diagnostic Routines

  1. 1) Analyze Vehicle Inspection/Maintenance (I/M) Test Report Ensure vehicle Inspection/Maintenance (I/M) test report has been analyzed. Check for data entry errors, correct model, year, vehicle test weight and correct calibration (California or Federal). Identify which gas readings are HIGH and which were LOW. If report includes a drive trace, identify during which mode the gas(es) failed. When report has been analyzed completely, go to next step.
  2. 2) 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.
  3. 3) Baseline Vehicle Using an exhaust gas analyzer, baseline 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). When vehicle has been baselined, go to next step.
  4. 4) Check For Other Symptoms Check for driveability concerns (including idle and A/T shifting concerns, exhaust smoke and for cooling system concerns (engine unable to reach normal operating temperature). If other symptoms are present, perform QUICK TEST in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. Repair as necessary, then go to step 40) to verify repairs. If no other symptoms are present, go to next step.
  5. 5) 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) to verify repairs. If no repairs are necessary and all checks are okay, go to next step.
  6. 6) Perform PCM Quick Test Perform QUICK TEST in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article to retrieve Diagnostic Trouble Codes (DTCs). If no DTCs are present, go to next step. If DTCs are present, service DTC. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - EEC-V - GASOLINE article to service appropriate DTC, then go to step 40) to verify repairs.
  7. 7) 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) .
  8. 8) 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) .
  9. 9) 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) .
  10. 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) to check for running rich concern.
  11. 16) Check Secondary Ignition System Go to TEST JB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article to check secondary ignition system. Follow diagnostic procedures and repair as necessary, then go to step 40) to verify repairs. If secondary ignition system is okay, go to next step.
  12. 17) Check Fuel Delivery System For High Fuel Pressure Or Leak-Down Check fuel delivery system. On Natural Gas models, go to TEST HB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. On all other models, go to TEST HC, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. Follow diagnostic procedures and repair as necessary, then go to step 40) to verify repairs. If fuel delivery system is okay, go to next step.
  13. 18) Check PCV System Check PCV system. Go to TEST HG, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. Follow diagnostic procedures and repair as necessary, then go to step 40) to verify repairs. If PCV system is okay, go to next step.
  14. 19) Check Exhaust System Check exhaust system. Go to TEST HF, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. Follow diagnostic procedures and repair as necessary, then go to step 40) to verify repairs. If exhaust system is okay, go to next step.
  15. 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) to verify repairs. If no engine mechanical problems are indicated and all checks are okay, go to next step.
  16. 21) Additional Checks Ensure correct PCV valve is installed for application. Service as necessary, then go to step 40) to verify repairs. If PCV valve is correct, go to step 45) .
  17. 25) High HC With Normal To Low CO Level, Check Fuel Delivery System For Leak-Down Or Low Fuel Pressure Check fuel delivery system for leak-down or low pressure. On Natural Gas models, go to TEST HB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. On all other models, go to TEST HC, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. Follow diagnostic procedures and repair as necessary, then go to step 40) to verify repairs. If fuel delivery system is okay, go to next step.
  18. 26) Check Secondary Ignition System Go to TEST JB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article to check secondary ignition system. Follow diagnostic procedures and repair as necessary, then go to step 40) to verify repairs. If secondary ignition system is okay, go to next step.
  19. 27) Check PCV System Go to TEST HG, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article to check PCV system. Follow diagnostic procedures and repair as necessary, then go to step 40) to verify repairs. If PCV system is okay, go to next step.
  20. 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) to verify repairs. If no engine mechanical problems are indicated and all checks are okay, go to next step
  21. 29) Additional Checks Ensure correct PCV valve is installed for application. Service as necessary, then go to step 40) to verify repairs. If PCV valve is correct, go to step 45) .
  22. 30) High NOx With Normal To Low HC & CO Levels Check engine for concerns such as excessive carbon build-up in combustion chamber. See appropriate article in ENGINES. Repair as necessary, then go to step 40) to verify repairs. If no engine mechanical problems are indicated, go to next step.
  23. 31) Additional Checks Check Torque Converter Clutch (TCC) operation. See appropriate OVERHAUL or ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS. Check intake air system for add-on aftermarket parts or modifications which may restrict airflow into intake air system. Check for running lean concerns (vacuum leaks or low fuel pressure), refer to procedures starting at step 25) . Repair as necessary, then go to step 40) to verify repairs. If all checks are okay, go to step 45) .
  24. 35) EVAP System Concern: Preliminary Checks Analyze 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) to verify repairs.
  25. 36) Perform PCM Quick Test Perform QUICK TEST in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article to retrieve Diagnostic Trouble Codes (DTCs). If no DTCs are present, go to next step. If DTCs are present, service DTC. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - EEC-V - GASOLINE article to service appropriate DTC, then go to step 38) to verify repairs.
  26. 37) Check EVAP Emissions System For Leaks See appropriate symptom in SYSTEM TESTS (EVAPORATIVE EMISSIONS) in SELF-DIAGNOSTICS - EEC-V - CNG & 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, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article, or return to «SYMPTOM DIAGNOSIS»(ref-40665-S19133719652001011200000) to repair any additional symptoms. Follow diagnostic procedures and repair as necessary, then go to step 38) .
  27. 38) EVAP Emissions System Repair Verification After making repairs to EVAP emissions system, reset KAM and relearn basic adaptive strategy. See KEEP ALIVE RANDOM ACCESS MEMORY RESET PROCEDURE under CLEARING CODES in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. Repeat PCM QUICK TEST. See QUICK TEST in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. Repair any DTCs that may be retrieved and perform EVAPORATIVE EMISSIONS SYSTEM LEAK TEST under SYSTEM TESTS (EVAPORATIVE EMISSIONS) in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. If original concern has not been corrected or if another concern exists, repeat step 1) .
  28. 40) Repair Verification After making repairs to appropriate system, reset KAM and relearn basic adaptive strategy. See KEEP ALIVE RANDOM ACCESS MEMORY RESET PROCEDURE under CLEARING CODES in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. Repeat PCM QUICK TEST. See QUICK TEST in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. Repair any DTCs that may be retrieved. Repeat 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). Ensure same drive mode is used as original baseline test performed in step 3) . If all gas levels are within acceptable range, save all repair documentation that may be required by local or federal law and return vehicle to customer. If any gas level is not within acceptable range, go to step 1) .
  29. 45) Catalyst Delta Temperature Test Disable 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 Coil On Plug 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, testing indicates catalytic converter is not operating correctly. 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) to verify repairs. 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. Perform PCM RESET PROCEDURE under CLEARING CODES in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. Repeat PCM QUICK TEST to clear any DTCs set during testing. See QUICK TEST in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. Verify previous test results. If results are okay, go to TEST Z, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. Follow diagnostic procedures and repair as necessary, then go to step 40) to verify repairs.

Check the following items

  1. On Pickups with Power Takeoff (PTO) and MIL concern, check PTO input to PCM. Go to TEST FB, step 3) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  2. If MIL is always on when engine is running and no DTCs are present, check MIL circuits. On Continental, Escape, Expedition, Focus, F150 Pickup, LS, Mustang, Navigator, Town Car or Windstar, see appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. On all other models, go to TEST NB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & 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, go to TEST TB, step 6) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & 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, Escape, Expedition, Focus, F150 Pickup, LS, Mustang, Navigator, Town Car or Windstar, see appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. On all other models, go to TEST NB, step 2) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & 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, go to TEST TB, step 8) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  6. If temperature warning indicator light or temperature gauge (models with CHT sensor) does not function properly, check cooling system or indicator light circuits. If engine is overheating, check and repair cooling system as necessary. If cooling system is operating at normal operating temperature, go to TEST DL, step 40) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  7. If SIL is always on or always off, check SIL circuits. Go to TEST KL, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  8. If fuel cap indicator light is always on or always off, check fuel indicator light circuits. On Continental, Escape, LS, Mustang, Town Car or Windstar, see appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. On all other models, if check fuel indicator light is always ON, go to TEST HX, step 88) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. For check fuel indicator light is always OFF, go to TEST HX, step 89) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  9. If no problems are indicated, return to «SYMPTOM DIAGNOSIS»(ref-40665-S19133719652001011200000) to identify any additional symptoms, or go to TEST Z, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article and check for intermittent faults.

Check A/T mechanical components and A/T shift solenoids and Torque Converter Clutch (TCC) solenoid operation. See appropriate OVERHAUL or ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS. If no problems are indicated, go to TEST Z, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article and check for intermittent faults.

Check the following items

  1. For tachometer inoperative on models with Clean Tach Output (CTO) circuit at PCM terminal No. 48, check CTO circuit from PCM. Go to TEST JH, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. To determine if CTO circuit is used, see appropriate PIN VOLTAGE/PID VALUE CHARTS article. Check terminal No. 48 under OUTPUTS.
  2. For speedometer/odometer inoperative on models with Manual Shift On-The-Fly (MSOF), check Transfer Case Speed Sensor (TCSS) circuits. Go to TEST DP, step 30) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. On all other models, check instrumentation. See appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT.

Check the following items

  1. Check PCV system. Go to TEST HG, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & 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.

Check the following items

  1. On Escort and Mustang, if cooling fan(s) do not operate at any speed, go to TEST X, step 40) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  2. On LS, if hydraulic cooling fan(s) do not operate at any speed, go to step TEST KH, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  3. On all other models, if cooling fan(s) do not operate at all speeds, go to TEST KF, step 25) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & 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, check cooling fan ACPSW or ACP circuits. Perform the following

  1. On Escort 2.0L and Mustang 4.6L, go to TEST X, step 80) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  2. On Mustang 3.8L, go to TEST X, step 82) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  3. On Continental and Windstar, go to TEST KF, step 63) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  4. On LS, go to TEST KH, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  5. On all other models, go to TEST KF, step 60) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  6. If no problems are indicated, check cooling system. See appropriate article in ENGINE COOLING.

Check the following items

  1. On Natural Gas models, check fuel delivery system for leaks. Go to TEST HB, step 16) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  2. On all models, check EVAP emission system for leaks. See SYSTEM TESTS (EVAPORATIVE EMISSIONS) in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.

A snap noise may be due to secondary ignition arcing. On Coil On Plug (COP) models, check condition of spark plug boots. On all other models, check secondary ignition system. Go to TEST JB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.

Check the following items

  1. On Mustang, go to TEST X, step 98) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & 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 a MANUAL or AUTOMATIC A/C-HEATER SYSTEMS article with Parameter Identification (PID) WACF displaying YES (fault indicated). See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article and follow diagnosis and repair for Key On Engine Off (KOEO) DTC P1460.

Check the following items

  1. On Mustang, go to TEST X, step 140) under SYSTEM TESTS in SELF DIAGNOSTICS - EEC-V - CNG & 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.

Check the following items

  1. On Mustang, go to TEST X, step 130) under SYSTEM TESTS in SELF DIAGNOSTICS - EEC-V - CNG & 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.

Check the following items

  1. Check fuel delivery system. On Natural Gas models, go to TEST HB, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article. On all other models, go to TEST HC, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.
  2. Check EVAP emission system for leaks. See SYSTEM TESTS (EVAPORATIVE EMISSIONS) in SELF-DIAGNOSTICS - EEC-V - CNG & 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 PCM setting a Diagnostic Trouble Code (DTC), 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 DTCs. Use test results to identify a faulty component or circuit. If no DTCs are present, check for intermittents. Go to TEST Z, step 1) under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG & GASOLINE article.

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