BMW M50B25 engine report, 325i E36
BMW M50B25 · 325i (E36)
2.5 LPetrolInline-61990–1995
82/100
Checked by hand
[good]
Only worth it at the right price
Worth buying, but only on the right car.
ExcellentGoodSolidRiskyAvoid
- Known issues
- 5
- Critical
- 1
- Sources
- 27
Verdict
These burn oil, and it comes up very often.
Ask how much gets topped up between services and check whether anyone has been tracking it. The VANOS solenoid is the other common trouble spot, usually not a disaster, but worth listening for on a test drive along with anything that feels rough. Oil leaks and the water pump are rarer and not cheap. Ringland failure is the one to actually fear, so unless the car is genuinely cheap and has been checked over properly, walk.
Specs
- Displacement
- 2.5 L
- Layout
- Inline-6
- Fuel
- Petrol
- Production
- 1990 – 1995
- Chassis
- E36
- Fitted
- 1990–1995
Known issues
5 confirmed · sorted by severity
CriticalPiston ringland failure
Piston ringland cracking under high cylinder pressure/heat, common on tuned forced-induction engines.
Symptoms
- Power Loss
- Smoke (White/Blue/Black)
- Misfire
How often
Occasional · Design weakness. Does not normally destroy the engine. Not safely drivable.
ModerateExcessive oil consumption
Worn valve stem seals, piston rings, or a clogged PCV/oil separator system causing oil consumption above manufacturer spec.
Symptoms
- Oil Consumption
- Smoke (White/Blue/Black)
How often
Very common · Age-related wear. Does not normally destroy the engine. Still drivable.
ModerateWater pump failure
Water pump seal or bearing failure (mechanical or electric pump), causing coolant loss.
Symptoms
- Coolant Loss
- Warning Light
How often
Rare · Age-related wear. Does not normally destroy the engine. Still drivable.
LowVariable valve timing solenoid/actuator failure
VANOS/VTEC/VVT-style variable valve timing solenoids or actuators fail or clog, causing rough idle, rattle on start, or reduced power.
Symptoms
- Rough Idle
- Reduced Power Mode
- Warning Light
How often
Common · Age-related wear. Can destroy the engine if ignored. Still drivable.
LowOil leak from seals or gaskets
Valve cover gasket, rear main seal, or front main seal degradation causing external oil leaks.
Symptoms
- Oil Consumption
How often
Rare · Age-related wear. Does not normally destroy the engine. Still drivable.
Check the car you're looking at
Owners rarely say at what mileage this engine's problems start, so they aren't sorted by mileage here. These are the ones to ask the seller about, the ones it's best known for first.
What to ask about
- Piston ringland failureHad this? Tell us at what mileage
- Excessive oil consumptionHad this? Tell us at what mileage
- Water pump failureHad this? Tell us at what mileage
- Variable valve timing solenoid/actuator failureHad this? Tell us at what mileage
- Oil leak from seals or gasketsHad this? Tell us at what mileage
Buying checklist
BMW M50B25 (325i E36) · Buying checklist
Sources
Updated 15 Sept 2026 · scoring v2.7
Behind this report sit 27 owner posts, forum threads and official records. Nothing gets on the list on one person's word. It takes a recall, or owners on separate platforms describing the same fault. The score then sets how often a problem turns up against the damage it does.