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Engine Controls - Tests W/o Codes - 7.5L Eec-Iv: Diagnosis Ford Pickup F350

Testing & Diagnostics ~2171 words

SYMPTOMS

Symptom checks cannot be used properly unless problem occurs while vehicle is being tested. To reduce diagnostic time, ensure that the BASIC DIAGNOSTIC PROCEDURES in BASIC TESTING - 7.5L article and SELF-DIAGNOSTIC TESTS in the TESTS W/CODES - 7.5L EEC-IV article were performed before diagnosing a symptom. 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. Fast 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. High Oil Consumption
  19. Exhaust Smoke
  20. Fuel Smell
  21. Engine Noise
  22. Vibration
  23. A/C System Always On

Symptom Checks

Perform the following

  1. Check starter relay.
  2. Check starting system.
  3. Check charging system.
  4. Check for seized/hydrostatic locked engine (leaking injectors).
  5. Check for defective flywheel/flexplate or seized engine components.
  6. Check ignition circuit. In particular, check for ignition starter wire shorting to ground.
  7. Check brake interlock switch (if equipped).
  8. Check transmission linkage adjustment or Transmission Range (TR) sensor adjustment. See ADJUSTMENTS in the TRANSMISSION SERVICING - AUTOMATIC article.

Perform the following

  1. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  2. Check fuel system/throttle body. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  3. Check for restricted exhaust system.
  4. Check cooling system for overheating (hard hot start only).
  5. Check Positive Crankcase Ventilation (PCV) system. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  6. Check Fuel Evaporation (EVAP) system. See EMISSION SYSTEMS & SUB-SYSTEMS in «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  7. Check starting system.
  8. Check Exhaust Gas Recirculation (EGR) system. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  9. Check for poor engine ground.

Perform the following

  1. Check for restricted exhaust system.
  2. Check for restricted air intake duct.
  3. Check EGR system. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  4. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  5. Check idle speed. See IDLE SPEED & MIXTURE in the «ADJUSTMENTS - 7.5L»(ref-23636) article.
  6. Check engine mechanical condition. Check compression, camshaft, valve train components, etc.
  7. Ensure transmission is functioning properly.
  8. Perform CIRCUIT TEST S in «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.
  9. If engine stalls during transmission engagement, check transmission solenoids. Go to CIRCUIT TEST TC in the «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.
  10. If engine stalls with A/C on, go to CIRCUIT TEST KM, step 10) in the «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.

Perform the following

  1. Perform CIRCUIT TEST AA in «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.
  2. Check for restricted exhaust system.
  3. Check engine mechanical condition. Check compression, camshaft, valve train components, etc.

Perform the following

  1. Check for throttle body contamination. Check for carbon build-up around throttle plate.
  2. Check air intake duct for leaks.

Perform the following

  1. Check RPM drop. See CIRCUIT TEST S, step 2) in the «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.
  2. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  3. Check idle speed. See IDLE SPEED & MIXTURE in the «ADJUSTMENTS - 7.5L»(ref-23636) article.
  4. Check fuel delivery and fuel pump. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  5. Check PCV system. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  6. Ensure engine operates at normal operating temperature.
  7. Check EGR system. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  8. Check engine mechanical condition. Check compression, camshaft, valve train components, intake manifold gaskets, etc.
  9. Check air injection. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  10. Check air intake system. Ensure throttle plate and linkages operate properly.
  11. Check Fuel Evaporation (EVAP) system. See EMISSION SYSTEMS & SUB-SYSTEMS in «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  12. Check for restricted exhaust system.

Perform the following

  1. Check idle speed. See IDLE SPEED & MIXTURE in the «ADJUSTMENTS - 7.5L»(ref-23636) article.
  2. Check air intake system. Ensure throttle plate and linkages operate properly.
  3. Check A/C system. See the «A/C-HEATER SYSTEM - MANUAL»(ref-23748) article.
  4. Ensure engine operates at normal operating temperature.

Perform the following

  1. For low idle symptom, disconnect IAC solenoid and check for RPM drop. If RPM does not drop, go to CIRCUIT TEST KE, step 4) in the «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.
  2. Check idle speed. See IDLE SPEED & MIXTURE in the «ADJUSTMENTS - 7.5L»(ref-23636) article.
  3. On A/T models, check transmission solenoids. See CIRCUIT TEST TC in the «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.
  4. Check Exhaust Gas Recirculation (EGR) system. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  5. If low idle exists with A/C on, go to CIRCUIT TEST KM, step 10) in the «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.

Perform the following

  1. Check power to MAP sensor. See CIRCUIT TEST S, step 3) in the «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.
  2. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  3. Check idle speed. See IDLE SPEED & MIXTURE in the «ADJUSTMENTS - 7.5L»(ref-23636) article.
  4. Check PCV system. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  5. Ensure driveline and transmission are functioning properly.
  6. Check air intake system. Ensure throttle plate and linkages operate properly.
  7. Check fuel delivery system. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  8. Check for restricted exhaust system.
  9. Check EGR system. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  10. Check Fuel Evaporation (EVAP) system. See EMISSION SYSTEMS & SUB-SYSTEMS in «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  11. Check engine mechanical condition. Check compression, camshaft, valve train components, etc.
  12. Check Heated Oxygen Sensor (HO2S) heater. See CIRCUIT TEST H, step 21) in «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.
  13. Check cooling system (radiator, thermostat, etc.)
  14. Check customer driving habits (over RPM/speed limiting function enabled).

Perform the following

  1. Ensure engine is operating at normal operating temperature.
  2. Check power to MAP sensor. See CIRCUIT TEST S, step 3) in the «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.
  3. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  4. Check idle speed. See IDLE SPEED & MIXTURE in the «ADJUSTMENTS - 7.5L»(ref-23636) article.
  5. Check Fuel Evaporation (EVAP) system. See EMISSION SYSTEMS & SUB-SYSTEMS in «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  6. If surge occurs with A/C on, check A/C clutch operation. See the «A/C-HEATER SYSTEM - MANUAL»(ref-23748) article.
  7. Check Fuel Evaporation (EVAP) system. See EMISSION SYSTEMS & SUB-SYSTEMS in «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  8. Check EGR system. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  9. Check air injection. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  10. Check air intake system. Ensure throttle plate and linkages operate properly.
  11. Check fuel delivery system. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  12. Check engine mechanical condition. Check compression, camshaft, valve train components, etc.
  13. Check Heated Oxygen Sensor (HO2S). See CIRCUIT TEST H, step 21) in the «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.
  14. Ensure speed (cruise) control system is functioning properly.

Perform the following

  1. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  2. Check air injection. See EMISSION SYSTEMS & SUB-SYSTEMS in «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  3. Check engine mechanical condition. Check compression, intake manifold gasket, camshaft, valve train components, etc.
  4. Check fuel delivery system. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.

Perform the following

  1. Check power to MAP sensor. See CIRCUIT TEST S, step 3) in the «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.
  2. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  3. Check fuel delivery system. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  4. Check for restricted exhaust system.
  5. Ensure engine operates at normal operating temperature.
  6. Check air intake system. Ensure throttle plate and linkages operate properly.
  7. Check engine mechanical condition. Check compression, camshaft, valve train components, etc.
  8. Ensure transmission is functioning properly.
  9. Check for binding/dragging brakes.
  10. Check customer driving habits.

Perform the following

  1. Check cooling system.
  2. Check base timing. See the «ADJUSTMENTS - 7.5L»(ref-23636) article.
  3. Check engine mechanical condition. Check compression, camshaft, valve train components, etc.
  4. Check fuel delivery system. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  5. Check EGR system. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  6. Check PCV system. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  7. Check air injection. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  8. Ensure transmission is functioning properly.

Perform the following

  1. Check fuel delivery system. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  2. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  3. Check for restricted exhaust system.
  4. Ensure engine is operating at normal operating temperature.
  5. Check EGR system. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  6. Ensure transmission is functioning properly.
  7. Check air injection. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  8. Check PCV system. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  9. Check for binding/dragging brakes.
  10. Check engine mechanical condition. Check compression, camshaft, valve train components, etc.

Perform the following

  1. Ensure engine operates at normal operating temperature.
  2. Check ignition system. See IGNITION SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  3. Check power to MAP sensor. See CIRCUIT TEST S, step 3) in the «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.
  4. Check idle speed. See IDLE SPEED & MIXTURE in the «ADJUSTMENTS - 7.5L»(ref-23636) article.
  5. Check PCV system. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  6. Check Fuel Evaporation (EVAP) system. See EMISSION SYSTEMS & SUB-SYSTEMS in «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  7. Check air injection. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  8. Check EGR system. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  9. Check engine mechanical condition. Check compression, intake manifold gasket, camshaft and valve train components, etc.

Perform the following

  1. Check if Malfunction Indicator Light (MIL) is on. Check instrument cluster as required.
  2. Check if 4x4 LOW or Transmission Control Indicator Light (TCIL) is on. Check instrument cluster as required.
  3. If MIL is never on, go to CIRCUIT TEST ML, step 2) in the «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.
  4. If MIL is on intermittently, go to CIRCUIT TEST ML, step 10) in «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.
  5. If MIL is flashing (erratic idle), go to CIRCUIT TEST ML, step 15) in «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.
  6. If 4x4 LOW indicator light always off, go to CIRCUIT TEST TB, step 4) in «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.
  7. If TCIL is always off, go to CIRCUIT TEST TB, step 6) in the «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.

Perform the following

  1. Check wiring harness connectors.
  2. Check for vehicle modifications.
  3. Check for electronic add-on items.
  4. Check for misadjusted shift linkage.

Perform the following

  1. Check PCV system. See EMISSION SYSTEMS & SUB-SYSTEMS in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) 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

  1. Check fuel delivery system. See FUEL SYSTEM in the «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  2. Check Fuel Evaporation (EVAP) system. See EMISSION SYSTEMS & SUB-SYSTEMS in «SYSTEM/COMPONENT TESTS - 7.5L EEC-IV»(ref-23717) article.
  3. Check canister purge solenoid. See CIRCUIT TEST KD in the «TESTS W/CODES - 7.5L EEC-IV»(ref-23602) article.

Perform the following

  1. Check radiator cooling fan.
  2. Check belt-driven components.
  3. Check engine mounts.
  4. Check crankshaft vibration damper.
  5. Check transmission.
  6. Check tires and wheels.
  7. Check driveline components.

Note. For additional A/C system information, see the A/C-HEATER SYSTEM - MANUAL article.

Perform the following

  1. Ensure A/C system (demand switch) is off. Disconnect A/C clutch and start engine. Check voltage at A/C clutch. If voltage is less than 2 volts, check A/C compressor and A/C system for malfunction.
  2. If voltage is more than 2 volts, check if A/C compressor can be turned off with A/C demand switch. If A/C compressor turns off, connect A/C manifold gauge set, and perform A/C system functional test.

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, 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.

More articles — Engine Controls - Tests W/o Codes - 7.5L Eec-Iv