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.
1985 Porsche 928 StandardFACTORY OEM SERVICE PROCEDURE
Throttle Switch (Idle)
- Pull off both EZF and LH control unit plugs. With LH control unit plug disconnected, connect ohmmeter between terminal 3 and ground. With throttle closed, reading should be zero ohms. With throttle open, reading should be infinite ohms.
- If values are not reached, repeat test direct on switch or on adapter plug. The throttle switch initiates coasting fuel shutoff. If circuit is open, there will be no coasting shutoff. If circuit is grounded, fuel will be shut off at fast idle speed.
Factory Service Tools
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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.