1991 Porsche 928 Problem Reports

Most Reported 1991 Porsche 928 Problem Reports

Report A Problem
View:Most ReportedNewestRepairPal Verified
A failing ECM or a fuel pump issue can cause a "No Start" condition.
Pay close attention to warning lights and have the brakes inspected regularly—immediately address any brake problems. Hard driving habits will cause excessive brake pad and rotor wear.
Timing belt life cannot be ascertained by inspection only. The timing belt and water pump must be maintained using the correct belt-adjustment tool. 

Intake air leaks at the manifold and elsewhere are common.

An alignment issue at the driveshaft/flex plate interface can cause a worn engine thrust bearing in the automatic transmission. Revised parts and assembly procedures are available.

Suspension components (including ball joints) are critical and require regular inspection.

The tire pressure monitoring system may have problems.

Mechanical wear in the clutch and clutch release mechanism can cause shifting engagement and noise issues.

The hydraulic fluid for the clutch system may be overlooked; the fluid should be replaced regularly during brake fluid service. If aging or contaminated fluid is not replaced, there may be problems in the lines and actuating components, as well as clutch issues that are difficult to diagnose.
Due to wear in the differential multi-disc clutch, the PSD (Porsche Slip Differential) locking system light may illuminate. The independent hydraulic fluid supply for the PSD needs to be maintained properly, including the filling/replacement of fluid before problems develop.
Due to electrical interference from cell phones and secondary ignition faults, the vehicle's central warning system display can be erratic.
Erratic switches and controls can cause electrical problems.
Aged and deteriorated connectors can cause common wiring issues; repair requires care and vehicle-specific information.