Diagnostic Aids
Check for any of the following conditions:
- Check the resistance of the EFI relay. There is continuity across terminals No. 1 and 2. The resistance across terminals No. 5 and 3 is infinite.
- The EFI relay electrical contacts may be pitted or sticking. Replace the EFI relay if tapping gently on the relay or wiggling the relay causes a change in the relay's operation.
- The performance of the EFI relay may be affected by temperature. Check the EFI relay after sitting outside overnight and after running the engine 30 minutes.
- If the EFI fuse opens during cranking, check for a shorted fuel pump/circuit. The EFI relay supplies current to the circuit opening relay that supplies power the fuel pump. The circuit opening relay is energized during cranking and when reference pulses are detected by the PCM.
An intermittent malfunction may be caused by a fault in the EFI relay electrical circuit. Inspect the wiring harness and components for an intermittent condition. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES - 1.8L VIBE article. For terminal identification, see Fig 1 .