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Problem Symptoms Table

PROBLEM SYMPTOMS TABLE - ENGINE CONTROL SYSTEM

Symptom Suspected Area
Engine does not crank (does not start)
  • 28. Starter
  • 29. Starter relay
No initial combustion (does not start)
  1. ECM power source circuit
  2. Fuel pump control circuit
  3. ECM
No complete combustion (does not start)
  1. Fuel pump control circuit
Engine cranks normally (difficult to start)
  1. Starter signal circuit
  2. Fuel pump control circuit
  3. Compression
Cold engine (difficult to start)
  1. Starter signal circuit
  2. Fuel pump control circuit
Hot engine (difficult to start)
  1. Starter signal circuit
  2. Fuel pump control circuit
High engine idle speed (poor idling)
  1. A/C signal circuit (Compressor circuit)
  2. ECM power source circuit
Low engine idle speed (poor idling)
  1. A/C signal circuit (Compressor circuit)
  2. Fuel pump control circuit
Rough idling (poor idling)
  1. Compression
  2. Fuel pump control circuit
Hunting (poor idling)
  1. ECM power source circuit
  2. Fuel pump control circuit
Hesitation/Poor acceleration (poor driveability)
  1. Fuel pump control circuit
  2. A/T faulty
Surging (poor driveability)
  1. Fuel pump control circuit
Engine stalls soon after starling
  1. Fuel pump control circuit
Unable to refuel/Difficult to refuel
  1. ORVR system