Q: Loss of power using turbo

asked by on May 19, 2016

My turbo isn't working - the car frequently drops down to a lower power level. For instance, I was on a long trip last week. The car started out driving okay, but then the power cut down, the engine light and engine management light lit up, and the glow plug light popped up. When I shut off the car, it reset the power. Stopping and restarting the engine restores the driving power (though the management light stayed on), but the glow-plug comes on and the power drops anywhere from a few seconds to a few minutes later. While I was driving back, the management light was still on, but the power stayed constant whether I was driving gently or pushing it. The dealership is recommending a new turbo, but these don't seem to point at my vanes sticking. What do you think? My local dealer has recommended a new turbo but these symptoms don't seem to me to be because the vanes are sticking. Any ideas?

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It sounds like the vehicle is going into limp mode. This occurs when the powertrain control module (PCM) (also known as the electrical control unit) has determined there is an overboost condition. The computer disables the turbo to prevent damage from occurring. There are many potential causes for an overboost condition, with a failed turbo being just one of them.

Some other possibilities include vacuum leaks, a faulty vane adjustment solenoid, faulty turbo actuator or a bad MAF sensor. There is a technical service bulletin (TSB) # 21-07-65, which advises to check for vacuum leaks before replacing the turbo.

If you would like a second opinion from the dealer, I suggest you give the team at YourMechanic a call to inspect your loss of power condition.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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