PGM-FI System

DTC Troubleshooting (cont'd)

11-258  

DTC 71: No. 1 Cylinder Misfire

DTC 72:

No. 2 Cylinder Misfire

DTC 73:

No. 3 Cylinder Misfire

DTC 74:

No. 4 Cylinder Misfire


  1. Reset the ECM/PCM (see page 11-168).
  2. Start the engine, and listen for a clicking sound at the injector at the problem cylinder.

Does it click?

YES

- Go to step 3.

NO

- Go to step 30.


  1. Turn the ignition switch OFF, and reset the ECM/PCM.
  2. Exchange the ignition coil from the problem cylinder with one from another cylinder.
  3. Start the engine. Hold the engine at 3,000 rpm (min-1) with no load (in park or neutral) until the radiator fan comes on, then let it idle with the headlights, rear defogger, blower fan and air conditioner turned off.
  4. Jump the SCS line (see step 2 on page 11-167).
  5. Test-drive the vehicle several times under various conditions.

Is DTC 71, 72, 73 or 74 indicated?

YES

- Go to step 8.

NO

- Intermittent misfire due to poor contact at the ignition coil connector (no misfire at this time).


  1. Determine which cylinder had the misfire.

Does the misfire occur in the other cylinder whose ignition coil was exchanged?

YES

- Replace the faulty ignition coil (see page 4-24).

NO

- Go to step 9.


  1. Turn the ignition switch OFF and reset the ECM/PCM.
  1. Exchange the spark plug from the problem cylinder with one from another cylinder.
  2. Test-drive the vehicle several times under various conditions.

Is DTC 71, 72, 73 or 74 indicated?

YES

- Go to step 12.

NO

- Intermittent misfire due to spark plug fouling, etc. (no misfire at that time).


  1. Determine which cylinder had the misfire.

Does the misfire occur in the other cylinder whose spark plug was exchanged?

YES

- Replace the faulty spark plug.

NO

- Go to step 13.