325i / 330i 3.0 (N52)

2005–2011 · petrol · 2996cc · 272hp

Engine codes: N52

Reliable

Reliability, common problems and owner reviews for the Bmw 3 Series E90 325i / 330i 3.0 (N52). Check this before you buy used.

The larger naturally-aspirated straight-six — strong, smooth and dependable like its 2.5 sibling. Same cooling-system and gasket wear items; no major design flaws. One of the best E90 engines to own.

Same engine, other cars

This is the same physical engine (N52) sold under different names across brands. Reliability is broadly shared — cross-check these:

Known Issues

Electric water pump failurerecurring

Electric water pump fails with age.

Fix / Workaround: Replace proactively (pump + thermostat).

Repair cost: €300–€700

Typically appears after: 130,000 km

Oil leaks (gaskets)recurring

Valve cover / oil filter housing gaskets leak.

Fix / Workaround: Replace gaskets.

Repair cost: €150–€600

Electric water pump and thermostat failurerecurring

The N52's electric water pump is a known service item — it fails without much warning between roughly 120,000 and 180,000 km, usually together with the electronically-controlled thermostat. Failure means overheating within minutes, and the magnesium-aluminium block does not forgive overheating.

Fix / Workaround: Replace pump + thermostat proactively around 150,000 km or at the first slow-warm-up / overheat warning. Not a cheap part, but far cheaper than a cooked engine.

Repair cost: €450–€900

Typically appears after: 120,000 km

Valvetronic eccentric shaft sensor and oil leaksrecurring

Two classic N52 age items: the Valvetronic eccentric shaft sensor fails (rough running, limp mode), and the valve cover + oil filter housing gaskets harden and leak oil — sometimes onto the belt and alternator below. Lifter tick on cold start at high mileage is also common and mostly benign.

Fix / Workaround: Budget for valve cover and oil filter housing gaskets on any 150k+ example; eccentric shaft sensor is a valve-cover-off job — do them together.

Repair cost: €300–€800

Typically appears after: 140,000 km

Mileage Thresholds

After 250,000 km: Long-lived with upkeep.

After 150,000 km: Do the electric water pump + thermostat proactively here if there's no record of them being changed — the single most important N52 preventive job.

Fault Codes to Scan

P0128Coolant temperature below thermostat regulating temperature — failing electronic thermostat.recurring

P0011Intake camshaft timing over-advanced — VANOS solenoid contamination; often fixed by cleaning/swapping solenoids.minor

P0301Cylinder misfire — coils and plugs age; on high-mileage cars also check the Valvetronic system.minor

Pre-Purchase Checklist

☐Water pump history
☐Oil-leak inspection
☐Excellent choice

Frequently asked questions

Is the Bmw 3 Series E90 325i / 330i 3.0 (N52) reliable?

Reliable — The larger naturally-aspirated straight-six — strong, smooth and dependable like its 2.5 sibling. Same cooling-system and gasket wear items; no major design flaws. One of the best E90 engines to own.

What are the common problems and reviews for the Bmw 3 Series E90 325i / 330i 3.0 (N52)?

The most commonly reported problems: Electric water pump failure, Oil leaks (gaskets), Electric water pump and thermostat failure, Valvetronic eccentric shaft sensor and oil leaks.

Is a used Bmw 3 Series E90 325i / 330i 3.0 (N52) worth buying?

Minor issues only, easy to maintain, no design flaws. A safe used buy.