BMW 5 Series E28 (1981–1988) — common faults, maintenance guides and repair tips.
The canister on the side of the distributor adjusts ignition timing. One hose goes to a vacuum point on the intake manifold and the other to the throt...
The pump is under the car in front of the tank on the right, next to the fuel filter. The fuel pump relay is in the engine bay next to the fuse box, a...
The most common cause is a faulty viscous fan (a fan that engages according to temperature) that does not engage. Cooling then relies entirely on the ...
The E28 has a hydraulic brake booster, not a vacuum booster. The most common cause is a faulty pressure accumulator, or brake bomb, whose diaphragm le...
The most common cause is a warped brake disc. The shudder can also come from a worn bushing that pumps when braking. Check the hub runout and the cali...
The causes can be a worn flex joint (rag joint), a torn centre bearing or centre support, the rear wheel bearings, or a loose heat shield rubbing agai...
The most common cause is an oxidised connector or a broken wire, often in the wiring boot between the door and the body. The door microswitch can also...
When cold the engine needs extra fuel and extra air. If a part related to enrichment is faulty, the fault shows only when cold. The suspects are the c...
The cause is usually a leaking master cylinder by the pedal or slave cylinder on the side of the gearbox. The seals wear with age and fluid leaks out,...
The core can leak coolant into the duct in the driver's footwell. A clogged core also weakens the heating: the E28 has no filter before the core, so s...
Most often the fault is in the temperature sensor, its wiring or the C101 connector on the side of the fuse box. A poor connection in the connector is...
The most common cause is a faulty voltage regulator, meaning the carbon brushes at the back of the alternator. On a Bosch alternator the regulator com...
The cluster circuit board has small backup batteries that leak as they age and corrode the board. As a result the solder joints oxidise or come loose....
Common causes are an air leak or a mixture that is too lean, and an ignition fault. A broken spark plug wire can cause jerking specifically under load...
The rattling often comes from the blower fan blades rubbing against the housing. You can see the cause by taking the blower plate off and turning the ...
The most common cause is the wiper motor's position sensing, which has become dirty with old grease. Cleaning fixes most of the symptoms. Also lubrica...
The coil's primary winding resistance is about 0.82 ohms and the secondary winding about 8250 ohms. The inductive sensor in the distributor (which tel...
The tank is 70 litres in all E28 models. If the gauge shows clearly less after a full tank, the cause is often the sender: the float may be stuck or t...
The most common cause is an intake leak: a cracked vacuum hose, breather hose, intake manifold gasket, or the rubber boot between the air flow meter a...
Cold. A clearance that is too small when warm can stop the valve from closing properly. The correct value varies by engine and source, so check it aga...
The typical cause is the electric water valve, which seizes with age. The same symptom can also be caused by the heater control unit or the interior t...