320d 2.0d (M47TU common rail)
2001–2006 · diesel · 1995cc · 150hp
Engine codes: M47D20, M47TUD20
Reliability, common problems and owner reviews for the Bmw 3 Series E46 320d 2.0d (M47TU common rail). Check this before you buy used.
The 150 hp M47 (E46, 2001–2006) is the common-rail generation: much quieter and stronger than the VP44 engine, but it brought intake swirl flaps — the single biggest risk on a used one, because a broken flap drops into a cylinder and destroys the engine. It is also known for turbo failures and soot-clogged EGR and intake. The engine is otherwise tough; a car with the flaps removed, a healthy turbo and short oil intervals is a sound buy, an unknown one is a gamble.
Known Issues
The common-rail M47TU has metal swirl flaps on spindles in the intake manifold. With soot build-up and wear a flap or its screw can break off and drop into a cylinder — the piston, head and often the turbo are destroyed, a repair worth more than most E46/E39 diesels.
Fix / Workaround: Remove the flaps and fit blanking plugs (with new manifold gaskets) or fit flaps from a known-good revised set. Check at purchase whether it has been done.
Repair cost: €80–€300
Typically appears after: 150,000 km
The turbo is the classic M47 failure (oil starvation, stretched oil intervals, worn bearings); the EGR valve and intake manifold clog with soot; the mass air-flow meter drifts and the car goes into limp mode.
Fix / Workaround: Short oil intervals with the correct oil, clean the intake and EGR, replace the MAF with a genuine unit. A new turbo without finding the oil-feed cause fails again.
Repair cost: €400–€1200
Typically appears after: 180,000 km
Common-rail injectors wear (hard starting, smoke, rough idle); glow plugs seize in the head.
Fix / Workaround: Leak-off test the injectors; free glow plugs with penetrating oil when warm before they snap.
Repair cost: €300–€900
Typically appears after: 200,000 km
On manual cars the dual-mass flywheel rattles at idle and judders when pulling away.
Fix / Workaround: Replace DMF and clutch together.
Repair cost: €600–€1100
Typically appears after: 180,000 km
Mileage Thresholds
After 150,000 km: Swirl flaps must be removed or verified by here.
Pre-Purchase Checklist
- ☐Ask whether the swirl flaps have been removed and blanked — see the invoice
- ☐Turbo shaft play, whistle, oil in the boost hoses
- ☐Cold start: injector rattle and smoke
- ☐DMF rattle at idle (manual)
Frequently asked questions
Is the Bmw 3 Series E46 320d 2.0d (M47TU common rail) reliable?
History-Dependent — The 150 hp M47 (E46, 2001–2006) is the common-rail generation: much quieter and stronger than the VP44 engine, but it brought intake swirl flaps — the single biggest risk on a used one, because a broken flap drops into a cylinder and destroys the engine. It is also known for turbo failures and soot-clogged EGR and intake. The engine is otherwise tough; a car with the flaps removed, a healthy turbo and short oil intervals is a sound buy, an unknown one is a gamble.
What are the common problems and reviews for the Bmw 3 Series E46 320d 2.0d (M47TU common rail)?
The most commonly reported problems: Intake swirl flaps (common-rail M47TU), Turbo, intake soot and EGR, Injectors and glow plugs, Dual-mass flywheel and clutch.
Is a used Bmw 3 Series E46 320d 2.0d (M47TU common rail) worth buying?
The engine itself is OK; condition is everything. Unknown or patchy history = walk away.