Car · Problems

Blue smoke from exhaust

Blue smoke is oil burning in the cylinders or exhaust. On a turbocharged engine, the turbo is the first suspect.

UrgencyModerate
Can I drive?Yes, carefully
Likely causesFailing turbocharger

Likely causes

  1. Failing turbocharger50%

    A whistle rising with revs, blue smoke and power loss are the classic trio of a dying turbo.

    Garage price: Turbocharger £730 – £1,780
  2. Oil level too low20%
    Garage price: Oil and filter change £70 – £150Fix it: Change your car's engine oil
  3. Head gasket30%

    Thick sweet white smoke, mayonnaise under the oil cap and coolant dropping with no visible leak.

    Garage price: Head gasket £590 – £1,560

What you can check yourself

  1. Check the oil weekly: burning more than a litre per 1,000 km is abnormal.

Fault codes often linked

P0045 Turbo boost control solenoid circuitP0234 Turbocharger overboost conditionP0236 Turbo boost sensor A range or performanceP0299 Turbocharger underboostP0010 Intake camshaft actuator circuit (bank 1)P0011 Intake camshaft timing over-advanced (bank 1)P0521 Engine oil pressure sensor range or performanceP0524 Engine oil pressure too low

Frequently asked questions

Blue smoke from exhaust: what causes it?

Likely causes: failing turbocharger (50%), oil level too low (20%), head gasket (30%).

Can I drive?

Yes, carefully. Urgency: moderate.

Indicative estimate. MecaScan cannot see your vehicle: always have a diagnosis confirmed by a professional, and never work on brakes, steering or airbags without the skills.