BMW E36/ E46 3 Series
Nigel Clark shows you how to look after your Beemer at home
SAVE £300 ENGINE 1 Code read E36
It’s good to start by checking for stored fault codes, so any issues can be tackled during the service.
The E36 models have a unique 20-pin OBD socket located just behind the right suspension turret.
Use an appropriate adaptor to connect the scanner.
2 Code read E46
Plug a universal 16-pin OBD2 scanner into the socket under the right side of the dashboard, near the accelerator pedal. Turn the ignition on, select the relevant model on the scanner and check for any fault codes stored in the ECU.
3 Undertray
The underside of the engine should be covered by an undertray. A hinged flap gives easy access to the sump plug but for a full service, remove the undertray. It’s secured by three plastic press fixings at the front and seven self-tapping screws at the sides and rear.
4 Oil change
Drain the oil with the engine fully warm. With a 10-litre drain pan at the ready, undo the sump plug. When the oil has drained completely, refit the plug with a new copper washer and tighten to the specified torque.
5 Oil filter change
Prepare for spillage and undo the top with a large socket or cup wrench. Pull out the old filter and then replace the large O-ring around the top and the small one on the tip of the filter’s locating spindle. Press the new filter into the lid and refit. Tighten to 10Nm.
6 Air filter change
Remove the air duct from above the radiator. Undo the spring clips around the top of the air filter housing and lift to remove the old filter. Vacuum dirt out of the filter housing before fitting a new filter and reattaching the lid and duct.
7 Cabin filter change
The cabin filter is often overlooked. E46 models have their filter beneath a cover on the bulkhead. The E36 has its filter either under the windscreen wiper scuttle or under the dash, below the heater.
8 Fuel filter change
Change the fuel filter every second Inspection 2 service for petrol cars. It’s behind a cover under the front passenger footwell. Relieve fuel pressure by removing the fuel pump fuse, then starting the engine until it stalls. Clamp the pipe ends before loosening the clips and change over the filter, being ready for some spillage.
9 Spark plug replacement: early four cylinder engines
The plugs and HT leads sit beneath a plastic cover on the cylinder head. Remove the cover, gently pull off the HT lead caps and remove each plug with a socket on a long extension. Fit new plugs without lubricating the threads, torque as specified, then refit the HT leads and cover.
10 Spark plug replacement: later four & six cyl engines
Remove the plastic covers on top of the engine, unplug wiring from each cylinder’s coil pack then undo coil packs’ securing bolts and remove.
Undo and remove the plugs. Fit new plugs and torque as specified, then refit the coil packs, wiring and engine covers.
11 Coolant
Drain, flush and replace the coolant at four yearly intervals. There’s a blue plastic drain plug beneath the expansion tank to the left of the radiator, and a second drain plug on the side of the cylinder block, behind the exhaust manifold.
THE NEXT STEPS… 12 Auxiliary drive belt
A serpentine ribbed drive belt powers the alternator, water pump and power steering from the crankshaft. On some models it also drives the aircon compressor. Inspect the ribbed surface and renew if there’s any sign of cracking or fraying; replace every four years regardless of appearance.
13 Air-con drive belt
Certain models have a separate belt to drive the aircon compressor, located in front of the serpentine auxiliary belt. Check condition and replace if necessary. Also inspect all pipe connections and hoses on the air-con system.
14 Brake fluid check and change
Replace the brake fluid if moisture is detected, or every two years regardless of mileage. Old fluid can be removed from the reservoir by pipette, then new fluid should be bled through to each caliper, thoroughly flushing out the old.
15 Manual gearbox
Check the gearbox for leaks. Remove the level plug on the side of the gearbox case and top up with Dexron III ATF if required. We recommend draining and refilling the gearbox at every Inspection 2 service.
16 Automatic gearbox
Inspect the auto ’box for fluid leaks. Though supposedly filled for life, we recommend changing fluid and filter every second Inspection 2 service. This requires removal of the gearbox sump when warm. Fresh ATF is introduced through a fill plug in the sump which has an internal weir to control fluid level.
17 Final drive oil
Inspect for leaking oil seals, and check the oil level by removing the level plug on the rear of the final drive unit, topping up if necessary. We recommend draining and replacing the oil at every Inspection 2 service. Also check driveshaft gaiters for splits.
18 Front brakes
Examine the front brakes, ensuring the pads have at least 3mm friction material remaining, and that the discs are not unduly worn or scored. Replace the discs if the wear ridge at the edge is more than 1mm deep. Check the brake hoses for chafing, cuts and blisters.
19 Front suspension
Inspect all joints and bushes thoroughly. Lower arm bushes and ball joints can wear, especially on six cylinder cars. The Macpherson strut top mounts are another potential wear point. Check the struts for signs of fluid leakage and coil springs for breakage.
20 Power steering inspection
Check the fluid level in the reservoir, topping up with ATF if required. Check for play in steering column joints, track rod ends and the steering rack itself. Inspect the rack gaiters for splits and check the pump and pipework for leaks.
21 Rear brakes
As with the front brakes, check the discs and pads for wear, and inspect the condition of the brake hoses. The metal brake pipes just inboard of the rear wheels are prone to corrosion, so check carefully.
22 Handbrake
The handbrake lever should travel eight or nine clicks to the fully on position. The handbrake operates via small shoes inside drums on the backs of the discs. There are knurled screw adjusters inside each drum, accessed through a wheel bolt hole.
23 Rear suspension
Check the rear suspension for worn bushes, broken coil springs and leaks from the shock absorbers. Shock absorber top mounts and trailing arm bushes are known wear points on the 3 Series BMWS.
24 Exhaust system
Check the entire length of the exhaust system for leakage, ensuring all mountings are in place and undamaged. Replacement of the exhaust gas oxygen sensor is recommended at 100,000 miles; it’s located low down on the exhaust manifold.
25 Refit wheels
Refit the wheels and check each one for play in hub bearings and suspension. Lower the car to the ground and torque the wheel bolts to 100Nm. Check and adjust the tyre pressures.
26 Reset service indicator
Reset the service indicator, using a reset tool in the OBD socket on the E36, or by turning the ignition key to position 1 and pressing the trip odometer button until the display enters reset mode on the E46.
27 Finish like a professional
The service is almost complete. Finish like a BMW main agent by carrying out a test drive and then washing and vacuuming the car. It’s now ready to face the next 15,000 miles!