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.
Step 4.0 Computed Timing Check: Introduction
This check tests the ability of the EEC-IV system to advance the timing. It also ensures the system is advancing the timing the amount the ECA "thinks it is".
The test occurs when the ECA advances the timing 20° +/- 3° over base for two minutes after the last code of the Engine Running (KOER) test is displayed. Timing is checked normally with a timing light.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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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