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Engine Controls - Tests W/o Codes - Eec-Iv (2.0L): Diagnosis Ford Probe II

Testing & Diagnostics ~3400 words

SYMPTOMS DIAGNOSIS

Symptom checks cannot be used properly unless problem occurs while vehicle is being tested. To reduce diagnostic time, ensure steps in BASIC TESTING - 4-CYL article and appropriate TESTS W/CODES - EEC-IV (2.0L) article in the ENGINE PERFORMANCE section 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 «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.
  7. Check ignition switch.
  8. Check transmission linkage adjustment.
  9. On models with distributor ignition, check for short to ground in starter wire.

Check the following items

  1. Perform QUICK TEST. See «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.
  2. Check ignition system. See IGNITION SYSTEMS in appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  3. Check fuel delivery system. See FUEL SYSTEM in appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  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 «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  8. Check starting system.
  9. Check EGR system. Refer to the appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  10. Check for contaminated MAF sensor.

Check the following items

  1. Perform QUICK TEST and check for codes. See «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If fault codes are present, perform appropriate CIRCUIT TEST.
  2. Check power to MAP/BARO sensor. See step 3) of CIRCUIT TEST S in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  3. Check Idle Air Control (IAC). See step 1) of CIRCUIT TEST S in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  4. Check idle speed. See IDLE SPEED in «ADJUSTMENTS - 4-CYL»(ref-22872) article in the ENGINE PERFORMANCE section below.
  5. Check ignition system. See IGNITION SYSTEMS in «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  6. If engine stalls during parking maneuvers, check Power Steering Pressure (PSP) switch operation. See step 3) of CIRCUIT TEST FF in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  7. If engine stalls during transmission engagement, check transmission solenoids. Go to CIRCUIT TEST TC in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  8. If engine stalls because of low fast idle (cold engine), proceed to to step 25) of CIRCUIT TEST KE in appropriate «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If engine has low idle or stalls with blower motor on, go to step 10) of CIRCUIT TEST FE. If engine has low idle or stalls with daytime running lights on, go to step 20) of CIRCUIT TEST FE. If engine has low idle or stalls with headlights on, go to step 30) of CIRCUIT TEST FE. If engine has low idle or stalls with rear window defroster on, go to step 40) of CIRCUIT TEST FE.
  9. Check for restricted exhaust system.
  10. Check for restricted air intake duct.
  11. Check EGR system. Refer to the appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  12. Check engine compression. Check engine mechanical condition. Check camshaft and valve train components.
  13. Ensure transmission is functioning properly.

Check the following items

  1. Perform QUICK TEST. See «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.
  2. Check ignition system. On models with Distributor Ignition (DI), perform CIRCUIT TEST AA. Refer to the appropriate «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. On all other models, perform CIRCUIT TEST AC.
  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 «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform 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 «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.
  2. Check ignition system. See IGNITION SYSTEMS in appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  3. Check idle speed. See IDLE SPEED in «ADJUSTMENTS - 4-CYL»(ref-22872) article in the ENGINE PERFORMANCE section.
  4. Check fuel pump. See FUEL SYSTEM in the appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  5. Check PCV system.
  6. Ensure engine operates at normal operating temperature.
  7. Check EGR system. Refer to the appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  8. Check engine compression. Check engine mechanical condition. Check intake manifold, manifold gasket, camshaft and valves.
  9. Check secondary air injection. Refer to appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  10. Check air intake system. Also, ensure throttle plate and linkages operate properly.
  11. Check Evaporative Emission (EVAP) system. Proceed to «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  12. Check charging system.
  13. Check exhaust system.

Check the following items

  1. Perform QUICK TEST. See «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.
  2. Check idle speed. See IDLE SPEED in «ADJUSTMENTS - 4-CYL»(ref-22872) article in the ENGINE PERFORMANCE section.
  3. On A/T models with overdrive, check transmission solenoids. See CIRCUIT TEST TC in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  4. Check EGR system. Refer to the appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  5. If engine has low idle or stalls when engine is cold (no fast idle), go to step 25) of CIRCUIT TEST KE in appropriate «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If engine has low idle or stalls with daytime running lights on, go to step 20) of CIRCUIT TEST FE. If engine has low idle or stalls with blower motor on, go to step 10) of CIRCUIT TEST FE. If engine has low idle or stalls with headlights on, go to step 30) of CIRCUIT TEST FE. If engine has low idle or stalls with rear window defroster on, go to step 40) of CIRCUIT TEST FE.

Check the following items

  1. Perform QUICK TEST. See «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.
  2. Check power to MAP/BARO sensor. See step 3) of CIRCUIT TEST S in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  3. Check ignition system. See IGNITION SYSTEMS in appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  4. Check idle speed. See IDLE SPEED in «ADJUSTMENTS - 4-CYL»(ref-22872) article in the ENGINE PERFORMANCE section.
  5. Check PCV system.
  6. Ensure driveline and transmission are functioning properly.
  7. Check air intake system. Also, ensure throttle plate and linkages operate properly.
  8. Check fuel delivery system. See FUEL SYSTEM in «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  9. Check for restricted exhaust system.
  10. Check EGR system. Refer to the appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  11. Check Evaporative Emission (EVAP) system. Proceed to «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  12. Check fuel delivery system. See FUEL SYSTEM in «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  13. Check engine compression. Check engine mechanical condition. Check intake manifold, manifold gasket, camshaft and valves.
  14. Check Heated Oxygen Sensor (HO2S) heater. Go to step 21) of CIRCUIT TEST H in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.

Check the following items

  1. Perform QUICK TEST. See «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.
  2. Check power to MAP/BARO sensor. See step 3) of CIRCUIT TEST S in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  3. Check ignition system. See IGNITION SYSTEMS in «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  4. Check idle speed. See IDLE SPEED in «ADJUSTMENTS - 4-CYL»(ref-22872) article in the ENGINE PERFORMANCE section.
  5. Check PCV system.
  6. If surge occurs with A/C on, check A/C clutch operation.
  7. Check Evaporative Emission (EVAP) system. See appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  8. Check EGR system. Refer to the appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article below in the ENGINE PERFORMANCE section.
  9. Check secondary air injection. Refer to appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  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 appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  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 21) of CIRCUIT TEST H in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  17. Ensure cruise control system is functioning properly.

Check the following items

  1. Check ignition system. See IGNITION SYSTEMS in «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  2. Perform QUICK TEST. See «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.
  3. Check secondary air injection. Refer to appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  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 appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.

Check the following items

  1. Perform QUICK TEST. See «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.
  2. Check power to MAP/BARO sensor. See step 3) of CIRCUIT TEST S in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  3. Check ignition system. See IGNITION SYSTEMS in appropriate «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  4. Check fuel delivery system. See FUEL SYSTEM in appropriate «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  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 engine compression. Check engine mechanical condition. Check intake manifold, manifold gasket, camshaft and valves.
  9. Ensure transmission is functioning properly.
  10. Check for binding/dragging brakes.
  11. Check EGR system. Refer to the appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  12. 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. Check base timing. See «ADJUSTMENTS - 4-CYL»(ref-22872) article in the ENGINE PERFORMANCE section.
  3. Perform QUICK TEST. See «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.
  4. Check engine compression. Check engine mechanical condition. Check intake manifold, manifold gasket, camshaft and valves.
  5. Check fuel delivery system. See FUEL SYSTEM in appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  6. Check EGR system. Refer to the appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  7. Check PCV system.
  8. Check secondary air injection. Refer to appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  9. Ensure transmission is functioning properly.
  10. If vehicle is equipped with a Octane Adjust shorting bar go to step 5) of CIRCUIT TEST KP in appropriate «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  11. Check oil quality.
  12. Check for exhaust leaks.

Check the following items

  1. Perform QUICK TEST. See «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.
  2. Check fuel delivery system. See FUEL SYSTEM in appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  3. Check ignition system. See IGNITION SYSTEMS in appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  4. Check for restricted exhaust system.
  5. Ensure engine operates at normal operating temperature.
  6. Check EGR system. See «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  7. Ensure transmission operates properly.
  8. Check secondary air injection. Proceed to appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  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 «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.
  2. Check ignition system. Refer to IGNITION SYSTEMS in «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  3. Check power to MAP/BARO sensor. See step 3) of CIRCUIT TEST S in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  4. Check idle speed. See IDLE SPEED in «ADJUSTMENTS - 4-CYL»(ref-22872) article in the ENGINE PERFORMANCE section.
  5. Check PCV system.
  6. Check Evaporative Emission (EVAP) system. Refer to «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  7. Check secondary air injection. Refer to «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  8. Check for restricted exhaust system.
  9. Check EGR system. Refer to the appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  10. Ensure engine operates at normal operating temperature.
  11. Check engine compression. Check engine mechanical condition. Check intake manifold, manifold gasket, camshaft and valves.

Check the following items on all models

  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 «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.
  3. If MIL never comes on, go to step 4) of CIRCUIT TEST ML in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  4. If MIL is flashing and engine idle is erratic, go to step 15) of CIRCUIT TEST ML in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  5. If MIL is on intermittently, go to step 10) of CIRCUIT TEST ML in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  6. If TCIL is always off, go to step 6) of CIRCUIT TEST TB in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.

Check the following items

  1. Perform QUICK TEST. See «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.

Check the following items

  1. Perform QUICK TEST. See «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform 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 «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.
  2. Check radiator cooling fan operation (if equipped). Start engine. Turn A/C on. Cooling fan should be on.
  3. If cooling fan does not operate, see step 10) of CIRCUIT TEST KF in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  4. Check base timing. See «ADJUSTMENTS - 4-CYL»(ref-22872) article in the ENGINE PERFORMANCE section.
  5. Check gauges/senders.
  6. Check for brake drag.
  7. Check transmission for overheating.
  8. Check for core sand in engine block.
  9. Check for internal cylinder block and cylinder head leaks.

Check the following items

  1. Check if radiator cooling fan runs continuously.
  2. Perform QUICK TEST. See «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.
  3. Check cooling system operation.
  4. Check temperature gauge and sender.

Check the following items

  1. Check fuel delivery system. See FUEL SYSTEM in appropriate «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  2. Check Evaporative Emission (EVAP) system. Proceed to «SYSTEM/COMPONENT TESTS - EEC-IV (2.0L)»(ref-22925) article in the ENGINE PERFORMANCE section.
  3. Perform QUICK TEST. See «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.

Check the following items

  1. Perform QUICK TEST. See «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform appropriate CIRCUIT TEST.
  2. 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 «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.
  3. If voltage is present to A/C clutch, connect A/C manifold gauges and perform A/C system function test.

Check the following items

  1. Ensure voltage does not exist at A/C clutch with A/C switch off.
  2. Perform QUICK TEST. See «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section. If code is present, perform 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 turned off during WOT, then turned back on a few seconds after returning to idle, system is functioning properly. If A/C system did not function as specified, go to step 60) of CIRCUIT TEST X in «TESTS W/CODES - EEC-IV (2.0L)»(ref-22880) article in the ENGINE PERFORMANCE section.

INTERMITTENT PROBLEM DIAGNOSIS

Intermittent fault testing requires duplicating circuit or component failure to identify the 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.

Use a DVOM to pinpoint faults. 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.

KOEO Wiggle Test

Connect test equipment. See TESTS W/CODES - EEC-IV (2.0L) article in the ENGINE PERFORMANCE section. 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 TESTS W/CODES - EEC-IV (2.0L) article in the ENGINE PERFORMANCE section.

KOER Wiggle Test

Connect test equipment. See TESTS W/CODES - EEC-IV (2.0L) article in the ENGINE PERFORMANCE section. 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 TESTS W/CODES - EEC-IV (2.0L) article in the ENGINE PERFORMANCE section.

More articles — Engine Controls - Tests W/o Codes - Eec-Iv (2.0L)