BMW 1.8i
Evolution of the M40 with chain timing. Frugal and long-lived; the typical weakness is the crankcase ventilation.
Roadster charm, no roadster bite
The 115 hp four-cylinder won't bring tears of joy in terms of straight-line performance. But the sub-1,200 kg weight and direct steering turn every corner into an experience — cruising with the sun on your face beats raw power.
Engine Weaknesses 5
Plastic thermostat housing and coolant hoses become brittle with increasing age. Thermostat failure leads to overheating, cracked hoses to sudden coolant loss.
Symptoms: Engine warms up slowly or overheats, coolant loss without visible leak, coolant level drops regularly.
The timing cover gasket is the most common source of oil loss on the M43B18. The cylinder head usually has to be removed in most cases — new head gasket kit, head bolts and valve cover gasket are then also due.
Symptoms: Oil patches under the engine, visible oil film on engine front face, oil smell in engine bay
Plastic coolant flanges at the rear of the cylinder head are a known weak point on the M43B18. They become porous with increasing age. Experts recommend replacing all flanges simultaneously.
Symptoms: Gradual coolant loss, coolant level drops without visible puddle under the vehicle
The oil filter housing tends to leak at the gasket to the engine block from about 120,000 km. Oil drips onto the hot exhaust manifold and creates smoke.
Symptoms: Blue smoke under the bonnet, oil smell in the cabin, visible oil trail on engine block below the oil filter.
Idle control valve of the M43B18 tends to foul through oil mist from crankcase ventilation. Rough idle often curable by cleaning with brake cleaner; with heavier wear replacement is required.
Symptoms: Fluctuating idle speed, rough engine at idle, engine stalls on gear changes
Vehicle Weaknesses 6
The fabric hood tears from years of folding and UV exposure and becomes leaky. Door seals also fail with age. The plastic rear window turns cloudy or develops folds.
Control arms, tie rod ends and ball joints on the front axle wear with higher mileage and are flagged at inspection. Typical issue on all E36-based vehicles.
The barrel bearings at the Z3 rear axle wear at higher mileage and must be replaced. An inexpensive repair that causes no consequential damage if done in time.
The VANOS unit on the six-cylinder engines (M52, M54) is prone to leaks and malfunctions. Worn seals and seized pistons in the VANOS system cause power loss and rough running.
The body-coloured mirror base rusts early on the Z3 and develops blisters. In severe cases the mirror can break off. Inexpensive fibreglass replacement bases are available.
Electric window regulators fail more frequently on the Z3. Cables or guide rails break, motors wear out. Typical age-related issue for late 1990s vehicles.
Reports & Tests
217 owner complaints filed with NHTSA (1995–2002). Most reported: Airbags (58), Seats (33), Seat Belts (33).