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Home >> Merkur >> 1988 >> Scorpio Standard >> Repair and Diagnosis >> Engine Performance >> System >> EEC-IV System >> Diagnosis By Symptom Test
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Diagnosis By Symptom Test

  1. When engine stalls, runs rough or misses, perform following checks or tests:
    • TEST S - SYSTEM CHECK  .
    • Check MAP sensor, using TEST DF - MAP/BP SENSOR  , step 11).
    • Check EGR operation.
    • Check fuel delivery.
    • Check for, and repair, any bad ground or power connections.
    • Check ignition components (cap, rotor, wires, coil and plugs).
    • Check basic engine components (valves, cam timing, compression, etc.).
  2. If gasoline fumes accumulate in engine compartment, go to TEST KD - CANP CHECK  .
  3. If fuel pump always runs, go to TEST J - INERTIA SWITCH  , step 11).
  4. If engine stumbles after hot restart, go to TEST HG - FUEL CONTROL  , step 15).
  5. If no A/C operation, go to TEST X - WOT/WAC SWITCH  .
  6. If no A/C cutout at WOT, go to TEST X - WOT/WAC SWITCH  , step 3).
  7. If no thermactor air management (manual only) go to TEST Z - AIR MANAGEMENT  .
  8. If CHECK ENGINE light is glowing, perform QUICK TEST  .