BMW 740Li Turbocharger

An internal combustion engine's efficiency and power output are increased by a turbocharger (or turbo), a turbine-driven forced induction device, by forcing more air into the combustion chamber. The compressor's ability to pump more air—and thus more fuel—into the combustion chamber than atmospheric pressure alone accounts for this increase in power output over a normally aspirated engine. A turbocharger's goal is to boost an engine's efficiency by raising the density of the intake gas (often air), which results in more power being produced each engine cycle.

Symptoms of turbocharger failure

There are several signs you can look out for to tell if your turbocharger has blown: 

• Loss of power
  Decreased engine power and acceleration.
• Excessive exhaust smoke
  Blue or black smoke indicating oil leaks.
• Unusual noises
  Whining or grinding sounds from the turbo.
• Check engine light
  Dashboard warning indicating potential turbo issues.
• Increased oil consumption
  Higher oil usage suggesting leaks from the turbo.
• Poor fuel economy
  Decreased fuel efficiency due to compensatory engine work.
• Overheating
  Higher engine temperatures affecting performance.