Vehicle
Porsche 928
The front-engined V8 grand tourer, and the most electrically complex Porsche of its era — which is where its diagnosis actually lives. Like the 944 it uses a rear transaxle and a torque tube, and like the 944 its V8 is a belt-driven interference engine whose timing belt is the single most consequential service item; a snapped belt is a rebuild. Beyond that, the recurring faults are age-related electrical: the LH-Jetronic and EZK control units suffer failed capacitors and cracked solder joints, producing running faults that chase like sensor problems and are not, and the central electrics board behind the dash corrodes. Check for a rebuilt module before condemning a sensor.
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Generations
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928 1977–1995
Front V8 with a rear transaxle; an interference belt engine, and failing capacitors in the LH-Jetronic and EZK units.
- Body styles
- Coupé
- Platform
- Porsche 928
- Engines
-
- 4.5 V8 — M28 · petrol
- 4.7 V8 — petrol · S
- 5.0 V8 — petrol · 430 Nm (317 lb-ft) · S4
- 5.4 V8 GTS — petrol · 500 Nm (369 lb-ft)
- Transmissions
- 5-speed manual · 4-speed automatic · 3-speed automatic
- Drivetrain
- Rear-wheel drive
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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