BMW 8-Series (E31)
Engines
Click the links below to see common problems specific to the engines available on this vehicle.
- BMW M60B40 (840Ci MY91-95)
- BMW M62B44 (840Ci MY96+)
- BMW M70B50 (850i)
- BMW M73B54 (850Ci)
- BMW S70B56 (850CSi)
Problems
All Vehicles
- Cooling system:
- Plastic radiators
- Expansion bottles – can split without warning
- Viscous fan – clutch-driven fan will wear out the viscous coupling and can cause temperatures to rise at idle; replacement of the viscous coupling is simple
- Hose that runs from the cooling system accumulator to the heater system bursts for no reason
- PCV valve – symptoms include smoke at start-up or under hard acceleration, and a noisy idle
- Inlet manifold seals – symptoms include noisy idle
- Manual transmissions – synchros are susceptible to damage if fluid other than Dexron II is used
Certain Vehicles
- Early models: problems with hazard lights and turn signals have been attributed to the flasher relay or crash sensor control module