KNOWN FAULTS · BMW

BMW Serie 3 (E46) 330d (M57) common problems.

2000–2006 · Diesel

Sources are not verified in real time and no entry confirms that your car is affected.

2 known faults with sources

Applies if: Only if the intake manifold has swirl flaps; some versions do not. Confirm at a garage.

Intake swirl flaps (M57)Intake

Engine / equipment: M57 3.0 six-cylinder diesel with swirl flaps (330d E46/E90, 525d/530d/535d E39/E60, 635d, 730d E65, X3 3.0d, X5 3.0d E53/E70, X6 30d/35d)
Period mentioned: 1998–2010
Symptoms: Usually none until it fails. A common early warning: oil seeping around the flap spindles on top of the engine. If a flap or its screw comes loose and enters a cylinder: sudden heavy knocking, loss of power, smoke and possible turbo damage as well.
Possible cause described: The metal flaps in the intake manifold collect soot and oil and their spindles wear over the years. The flap, its screw or part of the spindle can come loose and drop into the cylinder, damaging valves, piston and head. An owners' forum quotes BMW as having strengthened the spindles on later manifolds (from 4 to 4.5 mm), but other owners doubt the change removes the risk.
Check for the garage: At a garage: confirm whether the manifold has swirl flaps (some versions do not), look for oil around the spindles and play in the flaps, and check the history for earlier replacement or removal. With any new metallic knocking, stop the engine and do not restart it.
Cost cited in the source: Preventive inspection: workshop labour. If a flap enters the engine, a buyer's report quotes repair costs above €4,000.A rough figure from the original database, not an up-to-date quote.

Applies if: Weak points of this model from inspections, breakdown statistics and recalls; anything specific to one engine is stated in the sheet.

Rear axle mounting, suspension and airbags on the 3 Series E46Known weak points

Engine / equipment: BMW 3 Series E46 (petrol and diesel)
Period mentioned: 1998–2007
Symptoms: On cars built up to March 2000, the rear axle mounting can tear out of the body; worn wishbone bushes (noises and a nervous wheel under braking) and broken rear springs; hairline cracks in the expansion tank; oil pump on the six-cylinders; camshaft sensors, turbos and injection pumps; swirl flaps dropping into the cylinder on diesels; weak handbrake and porous brake pipes.
Possible cause described: At first BMW repaired the axle mounting with special foam or new floor panels as goodwill; today the repair is so expensive that it often is not worth it. Recalls: a passenger airbag that could burst (saloons May 1999 to August 2006) and gas generators in the sports steering wheel (November 1997–June 2000).
Check for the garage: On cars up to 2000, inspect the rear axle mounting area on a lift; check airbag campaigns by VIN.
Cost cited in the source: No verified estimate; ask the garage for a quote.A rough figure from the original database, not an up-to-date quote.