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Engine Controls - Tests W/o Codes - Eec-Iv (2.5L): Diagnosis Ford Contour I

Testing & Diagnostics ~2967 words

SYMPTOMS DIAGNOSIS

Symptom checks cannot be used properly unless problem occurs while vehicle is being tested. To reduce diagnostic time, ensure steps in the BASIC TESTING - 2.5L article and also in the appropriate TESTS W/CODES - EEC-IV (2.5L) 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. No Crank
  2. Hard Start/Long Crank
  3. Stalls After Start
  4. No Start/Normal Crank
  5. Slow Return To Idle
  6. Rough Idle
  7. High Idle (Diesels/Runs On)
  8. Low Idle (Stalls On Deceleration)
  9. Hesitates Or Stalls
  10. Surge (On Acceleration Or Cruise)
  11. Backfires
  12. Loss Of Power
  13. Spark Knock
  14. Poor Fuel Economy
  15. Emissions Compliance
  16. Warning Indicator Lights
  17. Improper Transmission Shift
  18. Tachometer Inoperative
  19. High Oil Consumption
  20. Engine Runs Hot
  21. Engine Runs Cold
  22. Exhaust Smoke
  23. Gas Smell
  24. Engine Noise
  25. Vibration
  26. Climate Control (Lack Of Cooling)
  27. Climate Control (A/C Always On)
  28. A/C Clutch Does Not Disengage Under WOT Conditions

Symptom Checks

Check the following items

  1. Check starter relay.
  2. Check starter circuit.
  3. Check charging circuit.
  4. Check for seized/hydro-locked engine (leaking injectors).
  5. Check for defective flywheel.
  6. Perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code is present, use appropriate CIRCUIT TEST.
  7. Check ignition switch.
  8. Check Transmission Range (TR) sensor adjustment. See ADJUSTMENTS in the TRANSMISSION SERVICING - A/T article in the TRANSMISSION SERVICING section.
  9. Check transmission linkage adjustment.
  10. On models with distributor ignition, check for short to ground in starter wire.

Check the following items

  1. Perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code is present, use appropriate CIRCUIT TEST.
  2. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  3. Check fuel delivery system. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  4. Check for restricted exhaust system.
  5. Check cooling system for overheating (hard hot start only).
  6. Check PCV system.
  7. Check Evaporative Emission (EVAP) system. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  8. Check starting system.
  9. Check EGR system. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  10. Check for contaminated MAF sensor.

Check the following items

  1. Perform QUICK TEST and check for codes. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If fault codes are present, perform appropriate CIRCUIT TEST.
  2. Check Idle Air Control (IAC). See step 1) of CIRCUIT TEST S in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  3. Check idle speed. See IDLE SPEED in «ADJUSTMENTS - 2.5L»(ref-23137) article.
  4. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  5. If engine stalls during parking maneuvers, check Power Steering Pressure (PSP) switch operation. See step 3) of CIRCUIT TEST FF in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  6. If engine stalls with A/C on, check A/C input circuit. See step 30) of CIRCUIT TEST KM in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  7. If engine stalls during transmission engagement, check transmission solenoids. Go to CIRCUIT TEST TC in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  8. Check for restricted exhaust system.
  9. Check for restricted air intake duct.
  10. Check EGR system. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  11. Check engine compression. Check engine mechanical condition. Check camshaft and valve train components.
  12. Ensure transmission is functioning properly.

Check the following items

  1. Perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code is present, use appropriate CIRCUIT TEST.
  2. Check ignition system. perform CIRCUIT TEST AC in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  3. Check for restricted exhaust system.
  4. Check engine compression. Check engine mechanical condition. Check intake manifold, manifold gasket, camshaft and valves.

Check the following items

  1. Perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code is present, use appropriate CIRCUIT TEST.
  2. Check for air leaks and throttle body contamination. Check for carbon build-up around throttle plate.

Check the following items

  1. Perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code is present, use appropriate CIRCUIT TEST.
  2. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  3. Check idle speed. See IDLE SPEED in «ADJUSTMENTS - 2.5L»(ref-23137) article.
  4. Check fuel pump. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  5. Check PCV system.
  6. Ensure engine operates at normal operating temperature.
  7. Check EGR system. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  8. Check engine compression. Check engine mechanical condition. Check intake manifold, manifold gasket, camshaft and valves.
  9. Check secondary air injection. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  10. Check air intake system. Also ensure throttle plate and linkages operate properly.
  11. Check Evaporative Emission (EVAP) system. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  12. Check charging system.
  13. Check exhaust system.
  14. Check Intake Manifold Runner Control (IMRC). See step 6) in CIRCUIT TEST KT in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.

Check the following items

  1. Perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code is present, use appropriate CIRCUIT TEST.
  2. Check idle speed. See IDLE SPEED in «ADJUSTMENTS - 2.5L»(ref-23137) article.
  3. On A/T models with overdrive, check transmission solenoids. See CIRCUIT TEST TC in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  4. Check EGR system. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.

Check the following items

  1. Perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code is present, use appropriate CIRCUIT TEST.
  2. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  3. Check idle speed. See IDLE SPEED in «ADJUSTMENTS - 2.5L»(ref-23137) article.
  4. Check PCV system.
  5. Ensure driveline and transmission are functioning properly.
  6. Check air intake system. Also ensure throttle plate and linkages operate properly.
  7. Check fuel delivery system. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  8. Check for restricted exhaust system.
  9. Check EGR system. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  10. Check Evaporative Emission (EVAP) system. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  11. Check fuel delivery system. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  12. Check engine compression. Check engine mechanical condition. Check intake manifold, manifold gasket, camshaft and valves.
  13. Check Heated Oxygen Sensor (HO2S) heater. Go to step 20) of CIRCUIT TEST H in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.

Check the following items

  1. Perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code is present, use appropriate CIRCUIT TEST.
  2. Check power to MAP/BARO sensor. See step 3) of CIRCUIT TEST S in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  3. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  4. Check idle speed. See IDLE SPEED in «ADJUSTMENTS - 2.5L»(ref-23137) article.
  5. Check PCV system.
  6. If surge occurs with A/C on, check A/C clutch operation.
  7. Check Evaporative Emission (EVAP) system. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  8. Check EGR system. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  9. Check secondary air injection. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  10. Ensure engine operates at normal operating temperature.
  11. Ensure transmission operates properly.
  12. Check for restricted exhaust system.
  13. Check air intake system. Also ensure throttle plate and linkages operate properly.
  14. Check fuel delivery system. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  15. Check engine compression. Check engine mechanical condition. Check intake manifold, manifold gasket, camshaft and valves.
  16. Check Heated Oxygen Sensor (HO2S) heater. Go to step 20) of CIRCUIT TEST H in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  17. Ensure cruise control system is functioning properly.

Check the following items

  1. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  2. Perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code is present, use appropriate CIRCUIT TEST.
  3. Check secondary air injection. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  4. Check engine compression. Check engine mechanical condition. Check intake manifold, manifold gasket, camshaft and valves.
  5. Check for restricted exhaust system.
  6. Check fuel delivery system. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.

Check the following items

  1. Perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code is present, use appropriate CIRCUIT TEST.
  2. Check power to MAP/BARO sensor. See step 3) of CIRCUIT TEST S in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  3. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  4. Check fuel delivery system. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  5. Check for restricted exhaust system.
  6. Ensure engine operates at normal operating temperature.
  7. Check air intake system. Also, ensure throttle plate and linkages operate properly.
  8. Check Intake Manifold Runner Control (IMRC). See step 6) of CIRCUIT TEST KT in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  9. Check engine compression. Check engine mechanical condition. Check intake manifold, manifold gasket, camshaft and valves.
  10. Ensure transmission is functioning properly.
  11. Check for binding/dragging brakes.
  12. Check EGR system. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  13. Ensure A/C turns off during Wide Open Throttle (WOT). If A/C does not turn off during WOT, go to A/C CLUTCH DOES NOT DISENGAGE UNDER WOT CONDITIONS symptom.

Check the following items

  1. Check cooling system for overheating. If cooling system is overheating, go to ENGINE RUNS HOT symptom.
  2. Perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code is present, use appropriate CIRCUIT TEST.
  3. Check engine compression. Check engine mechanical condition. Check intake manifold, manifold gasket, camshaft and valves.
  4. Check fuel delivery system. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  5. Check EGR system. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  6. Check PCV system.
  7. Check secondary air injection. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  8. Ensure transmission is functioning properly.
  9. If vehicle is equipped with an octane adjust shorting bar, go to step 5) of CIRCUIT TEST KP in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  10. Check oil quality.
  11. Check for exhaust leaks.

Check the following items

  1. Perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code is present, use appropriate CIRCUIT TEST.
  2. Check fuel delivery system. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  3. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  4. Check for restricted exhaust system.
  5. Ensure engine operates at normal operating temperature.
  6. Check EGR system. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  7. Ensure transmission operates properly.
  8. Check secondary air injection. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  9. Check PCV system.
  10. Check for dragging brakes.
  11. Check for contaminated Mass Airflow (MAF) sensor.

Check the following items

  1. Perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code is present, use appropriate CIRCUIT TEST.
  2. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  3. Check power to MAP/BARO sensor. See step 3) of CIRCUIT TEST S in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  4. Check idle speed. See IDLE SPEED in «ADJUSTMENTS - 2.5L»(ref-23137) article.
  5. Check PCV system.
  6. Check Evaporative Emission (EVAP) system. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  7. Check secondary air injection. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  8. Check for restricted exhaust system.
  9. Check EGR system. See the «SYSTEM/COMPONENT TESTS - EEC-IV (2.5L)»(ref-23172) article.
  10. Ensure engine operates at normal operating temperature.
  11. Check engine compression. Check engine mechanical condition. Check intake manifold, manifold gasket, camshaft and valves.
  12. Check HO2S heater secondary circuits. See step 40) of CIRCUIT TEST H in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  13. Check base ignition timing (if not already checked).

Check the following items

  1. If engine does not start, perform NO START/NORMAL CRANK symptom.
  2. Check if Malfunction Indicator Light (MIL), Transmission Control Indicator Light (TCIL) or Shift Indicator Light (SIL) is on. If any of the above indicator lights are on, perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code present, perform appropriate CIRCUIT TEST.
  3. If MIL never comes on, go to step 2) of CIRCUIT TEST ML in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  4. If MIL is flashing and engine idle is erratic, go to step 15) of CIRCUIT TEST ML in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  5. If MIL is on intermittently, go to step 10) of CIRCUIT TEST ML in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  6. If TCIL is always off, go to step 6) of CIRCUIT TEST TB in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  7. If TCIL is always on, go to step 3) of CIRCUIT TEST TB in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.

Check the following items

  1. Perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code is present, use appropriate CIRCUIT TEST.

Check the following items

* Perform QUICK TEST. See the TESTS W/CODES - EEC-IV (2.5L) article. If code is present, use appropriate CIRCUIT TEST.

Check the following items

  1. Check PCV system.
  2. Check engine mechanical condition. Check valves, valve guides, valve stem oil seals, intake manifold gaskets, cylinder head oil drain passages and piston rings.

Check the following items

  1. Perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code is present, use appropriate CIRCUIT TEST.
  2. Check radiator electric cooling fan operation (if equipped). Start engine. Turn A/C on. Cooling fan should be on.
  3. If one cooling fan motor is inoperative and the other cooling fan is functioning properly, go to step 50) of CIRCUIT TEST KF in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  4. If cooling fan does not operate, go to step 40) of CIRCUIT TEST KF in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.
  5. Check base timing. See the «ADJUSTMENTS - 2.5L»(ref-23137) article.
  6. Check gauges/senders.
  7. Check for brake drag.
  8. Check transmission for overheating.
  9. Check for core sand in engine block.
  10. Check for internal cylinder block and cylinder head leaks.

Check the following items

  1. Turn all accessories, A/C and defroster off. Check if radiator cooling fan runs continuously.
  2. Perform QUICK TEST. See the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article. If code is present, use appropriate CIRCUIT TEST.
  3. Check cooling system operation.
  4. Check temperature gauge and sender.
  5. If cooling fan is always on and no codes are present, go to step 25) of CIRCUIT TEST KF in the appropriate «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.

Check the following items

* Check fuel delivery system. See FUEL SYSTEM in the SYSTEM/COMPONENT TESTS - EEC-IV (2.5L) article.

* Check Evaporative Emission (EVAP) system. See the SYSTEM/COMPONENT TESTS - EEC-IV (2.5L) article.

* Perform QUICK TEST. See the TESTS W/CODES - EEC-IV (2.5L) article. If code is present, use appropriate CIRCUIT TEST.

Check the following items

* Perform QUICK TEST. See the TESTS W/CODES - EEC-IV (2.5L) article. If code is present, use appropriate CIRCUIT TEST.

* Ensure A/C system (demand switch) is on. Check voltage to A/C clutch. If voltage to A/C clutch is not present, go to step

1) of CIRCUIT TEST KM in the appropriate TESTS W/CODES - EEC-IV (2.5L) article. If voltage to A/C clutch is present, connect A/C manifold gauges and perform A/C system function test.

* If no A/C fault is indicated, check A/C Pressure Switch (ACPSW). Go to step 35) of CIRCUIT TEST KF in the TESTS W/CODES - EEC-IV (2.5L) article.

Check the following items

* Ensure voltage does not exist at A/C clutch with A/C switch off.

* Perform QUICK TEST. See the TESTS W/CODES - EEC-IV (2.5L) article. If code is present, use appropriate CIRCUIT TEST.

Check the following items

  1. Start engine. Turn A/C on. Perform a brief WOT and return to idle. If A/C system turns off during WOT and then turns back on a few seconds after returning to idle, system is functioning properly. If A/C system does not function as specified, go to step 15) of CIRCUIT TEST KM in the «TESTS W/CODES - EEC-IV (2.5L)»(ref-23138) article.

INTERMITTENT PROBLEM DIAGNOSIS

Intermittent fault testing requires duplicating circuit or component failure to identify problem. These procedures may lead to the computer setting a fault code (on some systems), which may help in diagnosis.

If problem vehicle does not produce fault codes, monitor voltage or resistance using a DVOM while attempting to reproduce conditions causing intermittent fault. A status change on DVOM indicates a fault has been located.

When monitoring voltage, ensure ignition switch is in ON position or engine is running. Ensure ignition switch is in OFF position or negative battery cable is disconnected when monitoring circuit resistance. Status changes on DVOM during test procedures indicate area of fault.

Continuous Monitor Mode (Wiggle Test)

In this mode, the technician can attempt to re-create an intermittent fault while monitoring the system. This mode, also called the wiggle test, may be used in Key On Engine Off (KOEO) and Key On Engine Running (KOER) self-test modes. See CIRCUIT TESTS in the TESTS W/CODES - EEC-IV (2.5L) article for instructions on the use of this procedure to identify intermittent faults in specific circuits or components.

KOEO Wiggle Test

Connect test equipment. See TESTS W/CODES - EEC-IV (2.5L) article. Turn ignition on. Activate self-test using jumper lead or diagnostic tester. Wait 10 seconds, and then deactivate and reactivate self-test to enter wiggle test. Tap, move and wiggle the suspected sensor and/or harness area. If a fault is detected, a code may be stored in memory and indicated at the diagnostic tester or scan tool. Record or retrieve code, and perform CIRCUIT TEST indicated in the TESTS W/CODES - EEC-IV (2.5L) article.

KOER Wiggle Test

Connect test equipment. See TESTS W/CODES - EEC-IV (2.5L) article. Turn ignition off and wait 10 seconds. Start engine. Activate self-test using jumper lead or diagnostic tester. Wait 10 seconds, and then deactivate and reactivate self-test to enter wiggle test. DO NOT turn engine off. Tap, move and wiggle the suspected sensor and/or harness area. If a fault is detected, a code may be stored in memory and indicated at the diagnostic tester or scan tool. Record or retrieve code, and perform CIRCUIT TEST indicated in the TESTS W/CODES - EEC-IV (2.5L) article.

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