Turbocharger

Car part Category: Engine DIY difficulty: Hard / Professional

What it is

A turbocharger uses exhaust gas to spin a turbine that forces extra air into the engine, making more power from a smaller engine. It spins at very high speed and runs extremely hot.

What it does

It boosts intake pressure so the engine can burn more fuel and make more power. A failing turbo causes loss of boost, whining or whistling, blue smoke (oil burning) and overboost/underboost codes such as P0234 and P0299.

Symptoms of failure

  • Overboost P0234 or underboost P0299 codes
  • Noticeable loss of power / limp mode
  • Loud whining or whistling that rises with boost
  • Blue/grey smoke from oil leaking into the intake or exhaust
  • Excessive oil consumption

Common fault codes

Which vehicles need it

Turbo petrol (EcoBoost, TSI) and most modern diesels. Oil starvation and worn seals are common failure causes.

Replacement cost

DIY (part only)$200–$800
At a shop (parts + labor)$1,200–$2,800
Replacement intervalNo set interval — protect it with clean oil and a cool-down; replace on failure.
DIY difficultyHard / Professional — exhaust, oil and boost plumbing; not a typical DIY job
Recommended brandsGarrett, BorgWarner, Mitsubishi (MHI), OEM

Where to buy the part

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Frequently asked questions

What kills a turbocharger?

Most turbo failures come down to oil — dirty oil, oil starvation, or coking from shutting a hot engine down too quickly. Worn bearings and seals then let oil into the intake and cause smoke and lost boost.

Can I drive with a P0299 underboost code?

Usually in limp mode, but you will have little power and may be making the problem worse (e.g. a boost leak or failing turbo). Get it diagnosed before driving far.

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