BMW 3 Series E30 (1982–1994) — common faults, maintenance guides and repair tips.
The most common causes are air trapped in the cooling system, a fan viscous coupling that does not engage, a stuck thermostat, a clogged radiator and ...
First check whether there is an ignition spark and whether fuel is arriving. If there is a spark, the fault is on the fuel side; if not, suspect the i...
The most common causes are the wheel sensor, its wire or connector, rust on the reluctor teeth (sensor ring), and the ABS relay and its fuse. An oxidi...
The most common cause is a vacuum leak: the engine gets air that the air flow meter does not measure, and the mixture goes too lean. Other causes are ...
The most common causes are a faulty pump relay, a blown fuse or a break in the wiring. An internal crack in the relay is common even if the relay and ...
Usually the cause is a seized brake caliper, brake hose or master cylinder. If the pedal sinks to the floor and the brakes do not hold, the master cyl...
Remove a spark plug, hold the plug lead attached to it and rest the plug body against metal. While someone cranks the engine, the spark is visible. At...
The fault is often in the central locking control box, which is on the driver's side behind the kick panel, low down under the speaker. The most commo...
A typical symptom is poor starting when a warm engine has stood for an hour or two. Right after shutting off there is usually no problem. Leaking inje...
The most common cause is an old sealed beam whose reflector surface has darkened or flaked; a new sealed beam improves the light output the most. Anot...
Common causes are air trapped in the heater core, heater core hoses connected the wrong way round, and a temperature control flap that does not close ...
The factory value is 0.25 mm for both the intake and exhaust valves. The adjustment is done on a completely cold engine, not after a few kilometres of...
Most often the cause is the connector or wire of the speed sensor at the rear of the car. The sensor is near the plug under the rear bumper. The wire ...
The rear shock absorber top mount rubbers may be completely worn out. Replacing the rubbers removes the rattle. A growl from the rear can instead come...
The play is usually caused by worn bushings and joints in the shift linkage. The gear lever's own bushing is usually the most worn. Also replace the m...
Disconnect the battery negative terminal and connect a multimeter or a small lamp between the terminal and the cable. Pull the fuses out one at a time...
With the ignition on, connect the temperature sensor wire to ground. If the needle jumps to full red, the gauge is fine and the fault is in the sensor...
The centre of a limited-slip differential is closed, whereas in a standard differential the differential gears are visible. You can also lift the rear...
The easiest way is to remove the whole subframe: disconnect the brake hoses, cables, driveshaft, shock absorbers and ABS wires. The old bushing is pul...
Signs include coolant loss, a sweet exhaust smell, bubbles in the radiator when you rev the engine, and mayonnaise-like oil. The symptoms alone do not...
The most likely fault is the carburettor's electronics. Using Pierburg's repair instructions, the carburettor has been made to work like new. New spar...
The oil comes from the rack's internal seals, which have worn loose. There should be no oil inside the boot. Replacing just the boot or using a fluid ...
The most likely cause is a leaking slave cylinder. It comes off its bracket with two 10 mm bolts. Replace only the slave cylinder first; the clutch di...
Open the meter's cover and wipe the carbon track with a lint-free cloth and alcohol or isopropanol. Do not use an electrically conductive substance or...
Typical places are the corners of the front footwells, the round service hatches in the footwells, the rear wheel housing around the fuel filler and v...
One cause is mounting screws that are too long for the cluster, which can cut the conductor tracks of the circuit board. Broken tracks can be repaired...
The cause may be dirty oil or filter. On an M20 engine, changing the oil filter and flushing the inside of the engine improved the situation, although...
Removing and fitting the ball joint requires a hydraulic press. Without a press, replacing the whole lower control arm is usually more sensible. The n...
Tapping with a socket is usually not enough. Use a puller or a press, or carefully knock the hub out from behind with a suitable tube. The bearing's i...
1. Remove the propeller shaft. 2. Loosen the sliding nut and separate the halves of the shaft. 3. Mark the halves so they are refitted in the same pos...
Usually poor gear contact inside the differential, often due to loose differential bearings. The fix is new bearings and adjusting the clearances and ...
Start with the battery terminals: a loose or dirty terminal clamp blocks the current even though the lights come on. Tighten and clean the clamps. The...
It is enough if the rest of the exhaust is in good condition. So first check the middle section and the mounts. The durability of aftermarket exhausts...
The descriptions and locations are in the car's owner's manual; at least the manuals of the 1988 and 1989 models have them. Not all models are exactly...
HC comes from incomplete combustion. The most common cause is an intake leak, the second most common is sensor faults. First check the vacuum hoses ru...
The most common leak point is the filler pipe joint on the side of the tank, at the right rear edge above the horizontal seam. The tank seams can also...
The check control light indicates low oil level. The oil light in the instrument cluster indicates oil pressure. The oil level sensor measures only th...
The pressure regulator is at the end of the fuel rail....