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 AutomaticFACTORY OEM SERVICE PROCEDURE
Fuel Pump
- The fuel pump relay (XX) is activated by a ground signal from the LH control unit and energizes the fuel pump. Connect terminal 17 of disconnected LH control unit plug to ground with a jumper wire.
- Turn ignition switch to the "ON" position. Fuel pump should be operating. If not, check fuse No. 42. If fuse is okay, bridge terminals 30 and 87 on fuel pump relay (XX). If relay does not activate, replace relay.
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.