Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Quick Test: Notes
The QUICK TEST diagnostic procedure is a functional test of the EEC-IV system. It consist of 4 basic test steps. These basic steps must be carefully followed in sequence, otherwise misdiagnosis, or replacement of non-faulty components may result.
Perform QUICK TEST as follows: Perform PREPARATION and EQUIPMENT HOOK-UP steps, KEY ON/ENGINE OFF (KOEO) SELF-TEST , TIMING CHECK , KEY ON/ENGINE RUNNING (KOER) SELF-TEST , and CONTINUOUS SELF-TEST . After all tests, servicing, or repairs have been completed, repeat QUICK TEST to ensure EEC-IV system works properly.
- The KEY ON/ENGINE OFF (KOEO) SELF-TEST is a static check of EEC-IV system inputs and outputs. The TIMING CHECK verifies the system's ability to compute and maintain a fixed spark timing during SELF-TEST.
- The KEY ON/ENGINE RUNNING (KOER) SELF-TEST is a dynamic system check with the engine under actual operating conditions and at normal operating temperature. The CONTINUOUS SELF-TEST checks the sensor inputs for opens and shorts while the vehicle is in operation.
- The KOEO and KOER SELF-TESTS are intended to detect faults present at the time of testing, not intermittent faults. Intermittent faults are detected by CONTINUOUS SELF-TEST .
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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