BMW 5 Series E34 (1988–1996) — common faults, maintenance guides and repair tips.
The most common cause is the main fuse. It is an aluminium strip in a black plastic housing under the rear seat, and it can have a thin crack, for exa...
The most common causes are a dirty or stuck idle control valve, a faulty throttle position sensor, a vacuum leak or a dirty mass air flow sensor (MAF)...
The most common cause is a stuck heater water valve. Other causes are no power to the valve, a broken circulation pump, air in the cooling system and ...
The most common causes are in the ignition: distributor cap and rotor, cracked ignition coils or a rubber boot (the sleeve leading to the spark plug) ...
The most common cause is air in the clutch hydraulics, especially after a clutch job. Bleed the hydraulics so that the fluid reservoir does not run em...
Check the pump relay first, then the power supply and ground, and finally the pump and fuel filter. The relay is a common cause: when cold, the relay ...
Often the oil level is too low or the filter is clogged. Slipping wears the clutch packs, so avoid driving. Simply topping up the oil is not enough: t...
Unplug the coils one at a time: if the running does not change, that coil is faulty. Another way is to swap a new coil in place of an old one, one at ...
The leak usually comes from between the pump covers, for example from the lowest cover or the injector line side. You can replace the cover gaskets yo...
The most common cause is the ignition: ignition coils, spark plugs or ignition wires. Other causes are the throttle position sensor, mass air flow sen...
On the M30, the piston rings should always be replaced and the ring grooves cleaned. Wear of the cylinders and pistons must be measured: if the cleara...
Yes. When the crankshaft position sensor fails, the engine management does not give power to the fuel pump and there is usually no spark. If there is ...
The top mount dimensions decide, not the model year or engine size. The surest way is to take the front strut down and measure the parts with calipers...
1. Raise the front of the car and open the expansion tank cap. 2. Fill with coolant, start the engine and set the heater fan to full. 3. Open the blee...
Typical causes are a worn idler arm bushing, a loose steering box, tie rod ends and the centre link. Also check the large nut on the steering column a...
The differential's metal ID plate is under a bolt on the rear cover, so brush it clean. The plate shows the ratio, and if it is preceded by the letter...
The most common causes are the strut top mount bearing, the lower control arm ball joint, drop links (the anti-roll bar links) and worn reaction rod b...
With a warm engine the needle is roughly in the middle, usually vertical or slightly past it. On highway driving it may be slightly below the centre l...
Signs are pressure and coolant loss in the cooling system, a heater that blows cold and bubbling in the expansion tank immediately on a cold start. Ha...
The cause can be the boot wiring harness or the boot lid switch. If the fault is intermittent, a wire or connector is probably faulty. If the brake li...
The most common cause is worn, intermittently breaking wires in the harness running next to the boot lid hinge. Also check the door grommets. Other ca...
PPPP is a data error that stays on the display, for example after the battery has been disconnected. 1. Disconnect the battery terminal for a moment. ...
The most common cause is too little refrigerant: the A/C buttons light up only when there is pressure in the system. The leak can be, for example, in ...
The cause is usually a sensor, bulb, connector or wiring. Cheap LED bulbs trigger the warning, and the brake pad wear warning can come on if the wear ...
The oxygen sensor generates its own voltage, so it is measured as voltage, not as resistance. With a warm engine at idle, the voltage on the signal wi...
The intake boot is the rubber tube between the mass air flow sensor and the throttle body. When it cracks, unmetered air enters the engine and the mix...
The cause is usually the wiper relay, a fault in the wiper switch (the stalk) or a fuse. The relay is in the relay module under the rear seat, and the...
Remove the sensor and spray air sensor cleaner (e.g. CRC Air Sensor Cleaner) onto the sensor and its flap. Check the sensor wire before cleaning. Clea...
First check the speed sensor connector and wires: an oxidised connector or a sensor wire broken at the base of the connector causes jumping or stoppin...
The specification is 0.30 mm for both intake and exhaust valves, measured on a cold engine. With a worn camshaft and rockers, 0.25 mm can be used beca...
There is vibration and a thumping noise under acceleration that grows with torque. A rattle is heard when pulling away. The driveshaft is rocked in fr...
The most common cause is the blower series resistor, which is located in the front passenger footwell. If the speed control does not work but the temp...
Severe running trouble or stalling is usually caused by one of two things: fuel is not arriving (pump or relay), or the engine management is not getti...
Measure the battery voltage and condition under load. Then check the grounds: the battery ground and the ground lead between the engine and the body c...
The E34 needs an ADS cable: reading with the INPA software requires it, a USB cable does not work and an E-ville cable is not suitable. INPA also need...
The breather ventilates the crankcase. On the M60, a torn breather valve or oil separator diaphragm lets oil vapor into the intake manifold. Symptoms ...
The most common causes are a warped front brake disc and a sticking brake piston. Also the radius arm bushings or ball joints can cause vibration, and...
The aluminium arm is lighter and reduces unsprung weight, and is usually also more expensive. The steel arm is heavier. A difference in durability has...