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.
Checking Ignition Change-Over
Connect timing light and tachometer and check ignition timing at idle, should be 5° ATDC. Connect wire of 212°F temperature switch to ground, ignition timing should advance by about 12° and engine speed should increase by about 200 RPM. Reconnect temperature switch wire and switch on air conditioning. This should also advance ignition and raise engine speed by about 100 RPM. If ignition retard is not cancelled, check two-way valve and relay.
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.