Diagnostic Aids

WARNING: This page is about a different car, the 1998 Mercury Tracer and 1998 Ford Escort. However, it is still accessible from the selected car via links, so may be relevant.

Test procedures are intended to identify faulty components or wiring while fault is present. If complaint is an intermittent condition, refer to TESTS W/O CODES article or CIRCUIT TEST Z in appropriate article:

For SOHC vehicles, see TESTS W/CODES .
For DOHC vehicles, see TESTS W/CODES .

Check For Diagnostic Trouble Codes (DTC)

Perform QUICK TEST. See appropriate article:
- For SOHC vehicles, see TESTS W/CODES .
- For DOHC vehicles, see TESTS W/CODES .
If DTCs are present, service codes as necessary. If codes are not present, go to next step.

Check Battery

Turn ignition on. Check battery voltage. If battery voltage is less than 12 volts, service battery as necessary. If battery voltage is more than 12 volts, go to next step.

Check For Spark

Using Spark Tester (D81P-6666-A Or D89P-6666-A), check for spark at each spark plug wire or coil while cranking. If spark is consistent at all spark plug wires, go to next step. If spark is not consistent, go to CIRCUIT TEST JD in appropriate article to test crankshaft position sensor:
- For SOHC vehicles, see TESTS W/CODES .
- For DOHC vehicles, see TESTS W/CODES .

Check Spark Plugs

Remove and inspect spark plugs. Replace plugs as necessary. If spark plugs are okay, testing is complete. If fault is still present, go to TESTS W/O CODES article. If vehicle has a no-start condition, go to CIRCUIT TEST A in appropriate article:
- For SOHC vehicles, see TESTS W/CODES .
- For DOHC vehicles, see TESTS W/CODES .