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Engine Controls - Tests W/o Codes: Other Mercury Villager I

Testing & Diagnostics ~1017 words

NO CRANK

  1. Check battery voltage.
  2. Check starting circuit.
  3. Check starter motor.
  4. Check for seized engine or damaged flywheel.

HARD START/LONG CRANK

  1. Check for vacuum leaks.
  2. Check ignition system. See «BASIC TESTING - 3.0L»(ref-23346) article.
  3. Check fuel delivery system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  4. Check idle air control systems. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  5. Check EGR system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  6. Check radiator cooling fan operation (hard, hot start only).
  7. Check engine compression and mechanical condition.

STALL AFTER START

  1. Check for vacuum leaks.
  2. Check idle air control systems. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  3. Check fuel delivery system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  4. Check EGR system. See «SYSTEM/COMPONENT TESTS»(ref-23366) and «TESTS W/CODES»(ref-23293) articles.
  5. Check PCV system.
  6. Check EVAP system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  7. Check ignition system. See «BASIC TESTING - 3.0L»(ref-23346) article.

NO START/NORMAL CRANK

CAUTIONExtended cranking can cause damage to catalytic converter. After repairing NO START condition, disconnect fuel injector connectors and crank engine until fuel is purged from exhaust system.
  1. Check ignition system. See «BASIC TESTING - 3.0L»(ref-23346) article.
  2. Check idle air control systems. See appropriate «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  3. Check EGR system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  4. Check fuel delivery system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.

SLOW RETURN TO IDLE

  1. Check for vacuum leaks.
  2. Check air intake system.
  3. Ensure throttle linkage operates properly.
  4. Ensure idle air control system operates properly. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  5. Check fuel delivery system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.

IDLE SURGE, RUNS ROUGH OR MISSES

  1. Check for vacuum leaks.
  2. Check idle air control systems See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  3. Check ignition system. See «BASIC TESTING - 3.0L»(ref-23346) article.
  4. Check fuel delivery system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  5. Check EGR system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  6. Check PCV system.
  7. Check engine compression and mechanical condition.

FAST IDLE, DIESELS/RUNS ON

  1. Ensure throttle plate and linkage operate properly.
  2. Check idle air control systems. See appropriate «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  3. Check for vacuum leaks.
  4. Check cooling system.

LOW/SLOW IDLE, STALLS/QUITS

  1. Check idle air control systems. See appropriate «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  2. Check fuel delivery system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  3. Check EGR system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.

STALLS/QUITS, HESITATION/STUMBLE

  1. Ensure base idle speed is correct. See «ADJUSTMENTS - 3.0L»(ref-23308) article.
  2. Check idle air control systems. See appropriate «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  3. Check ignition system. See «BASIC TESTING - 3.0L»(ref-23346) article.
  4. Check fuel delivery system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  5. Check EGR system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  6. Check engine compression and mechanical condition.
  7. Check exhaust system for leaks or restrictions.

RUNS ROUGH/MISSES

  1. Check ignition system. See «BASIC TESTING - 3.0L»(ref-23346) article.
  2. Check fuel delivery system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  3. Check EGR system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.

SURGES

  1. Check for vacuum leaks.
  2. Check idle air control systems. See appropriate «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  3. Check fuel delivery system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  4. Check EGR system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  5. Check EVAP system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.

BACKFIRES

  1. Check for vacuum leaks.
  2. Check ignition system. See «BASIC TESTING - 3.0L»(ref-23346) article.
  3. Check engine compression and mechanical condition.
  4. Check for leaking or restricted exhaust system.

LOSS OF POWER

  1. Check air intake system.
  2. Ensure throttle plate and linkage operate properly.
  3. Check ignition system. See «BASIC TESTING - 3.0L»(ref-23346) article.
  4. Check fuel delivery system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  5. Check for restricted exhaust system.
  6. Check engine compression and mechanical condition.
  7. On M/T models, ensure clutch is operating properly.
  8. On A/T models, ensure transmission is operating properly.
  9. Check for dragging brakes.

SPARK KNOCK

  1. Check ignition system. See «BASIC TESTING - 3.0L»(ref-23346) article.
  2. Check for vacuum leaks.
  3. Check EGR system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  4. Check cooling system for overheating.

POOR FUEL ECONOMY

  1. Ensure throttle plate and linkage operate properly.
  2. Check air intake system.
  3. Check fuel delivery system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  4. Check ignition system. See «BASIC TESTING - 3.0L»(ref-23346) article.
  5. Check for vacuum leaks.
  6. Check for restricted exhaust system.
  7. Check EGR system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  8. Check for slipping clutch.
  9. Check for dragging brakes.
  10. Check odometer calibration.
  11. Vehicle load, driving habits, road and weather conditions can also effect fuel economy.

EMISSIONS COMPLIANCE

If a vehicle fails an emission test, it is probable that catalytic converter was not hot enough immediately prior to the test, or the vehicle had idled excessively long prior to the test.

The following encompasses most of the emissions measurement modes of current state idle test procedures

  1. Ensure engine is at normal operating temperature and all accessories are turned off.
  2. Check emissions at idle.
  3. Operate engine at 2200-2800 RPM.
  4. Check emissions within 30 seconds.
  5. Return engine speed to idle.
  6. Check emissions within 30 seconds.

If any emission component is changed, PCM memory should be cleared before repeating state emission test procedure. See TESTS W/CODES article.

  1. Check ignition system. See «BASIC TESTING - 3.0L»(ref-23346) article.
  2. Check for vacuum leaks.
  3. Check fuel delivery system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  4. Check EGR system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  5. Check PCV system.
  6. Check EVAP system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  7. Check idle air control systems. See appropriate «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  8. Check for leaking or restricted exhaust system.
  9. Check condition of catalytic converter.
  10. Check cooling system.
  11. Check engine compression and mechanical condition.

WARNING INDICATOR LIGHTS

  1. If Malfunction Indicator Light (MIL) is on or flashing while driving, perform QUICK TEST. See «TESTS W/CODES»(ref-23293) article.

HIGH OIL CONSUMPTION

  1. Ensure engine oil is at proper level. Check for proper oil dipstick application.
  2. Check engine for external oil leaks.
  3. Check PCV system for restriction or worn PCV valve.
  4. Visually inspect exhaust for blue smoke, indicating worn piston rings.
  5. Check for engine oil contamination/dilution from fuel or coolant.

COOLING SYSTEM RUNS HOT

  1. Check cooling system for restrictions or leaks.
  2. Check cooling fan operation.
  3. Check temperature gauge accuracy.
  4. Check ignition timing.
  5. Check engine mechanical condition.

COOLING SYSTEM RUNS COLD

  1. Check cooling system thermostat.
  2. Check temperature gauge accuracy.

EXHAUST SMOKE OR SMELL

  1. Check air intake system. Ensure air filter is clean.
  2. Check fuel delivery system. Ensure no fuel injectors are leaking.
  3. Check PCV system.
  4. Check engine compression and mechanical condition.
  5. Check cooling system.

FUEL ODOR

  1. Check fuel delivery system. See appropriate «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  2. Check EVAP system. See «SYSTEM/COMPONENT TESTS»(ref-23366) article.
  3. Check PCV system.

Intermittent Simulation

To reproduce the conditions creating an intermittent fault, use the following methods

  1. Lightly vibrate components.
  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 attempting to simulate intermittent. Use the results to identify a faulty component or circuit.

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