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Problem Symptoms Table

WARNING: This page is about a different car, the 2005 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

When a malfunction is not confirmed by a DTC (Diagnostic Trouble Code) check and the cause of problem cannot be identified through a basic inspection, TROUBLESHOOTING according to the priority order indicated in the table below.

PROBLEM SYMPTOMS TABLE - ENGINE CONTROL SYSTEM (1GR-FE)

Symptoms Suspected Areas
Engine does not crank (Does not start)
  1. Immobilizer system
  2. Starter
  3. STARTER relay
No initial combustion (Does not start)
  1. ECM power source circuit
  2. Fuel pump control circuit
  3. ECM
Engine cranks normally but difficult to start
  1. Fuel pump control circuit
  2. Compression
Difficult to start with cold engine
  1. Starter signal circuit
  2. Fuel pump control circuit
  3. Spark plug
  4. Ignition system
  5. Injector
Difficult to start with warm engine
  1. Starter signal circuit
  2. Fuel pump control circuit
  3. Spark plug
  4. Ignition system
  5. Injector
High engine idling speed (Poor idling)
  1. A/C signal circuit (compressor circuit)
  2. ECM power source circuit
  3. Electronic throttle control system
  4. Air induction system
  5. PCV hose
Low engine idling speed (Poor idling)
  1. A/C signal circuit (compressor circuit)
  2. Fuel pump control circuit
  3. Electronic throttle control system
  4. Air induction system
  5. PCV hose
Rough idling (Poor idling)
  1. Compression
  2. Fuel pump control circuit
  3. Electronic throttle control system
  4. Air induction system
  5. PCV hose
Hunting (Poor idling)
  1. ECM power source circuit
  2. Fuel pump control circuit
  3. Spark plug
  4. Ignition system
  5. Injector
  6. Electronic throttle control system
  7. Air induction system
  8. PCV hose
Hesitation/Poor acceleration (Poor driveability)
  1. Fuel pump control circuit
  2. A/T faulty (A750E/A750F)
  3. Spark plug
  4. Ignition system
  5. Injector
Surging (Poor driveability)
  1. Fuel pump control circuit
  2. Spark plug
  3. Ignition system
  4. Injector
Engine stalls soon after starting
  1. Fuel pump control circuit
  2. Spark plug
  3. Ignition system
  4. Injector
Engine stalls during A/C operation
  1. A/C signal circuit (Compressor circuit)
  2. ECM
Unable/difficult to refuel Refueling valve (canister)
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