Peugeot 307 - Down on power, possibly Turbo waste gate?

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Mon 25 Apr 2011 00:10
Peugeot 307 - Down on power, possibly Turbo waste gate? - UJU

Ok, so I'm still having problems with my 307 DTurbo 2.0 HDi 110. Its down on power and it seems like often the turbo does not kick in. Im guessing the turbo is not kicking in because sometimes it accelerates really slowly and there is no turbo whistle. Whereas other times it pulls nicely and there is a high pitched whistle as the turbo spins happily. I've read about turbo wastegates getting stuck and causing these problems. Can anyone explain to me how the wastegate works and how I go about checking it and fixing it if needed on my car.

Thanks very much in advance.

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Sat 28 May 2011 17:21
Peugeot 307 - Down on power, possibly Turbo waste gate? - E1982

First of all I will explain what the wastegate is and its function, secondly i will tell you how it is operated on peugoets.

A turbo wastegate is essentially a pressure release valve, when you start to rev the engine the exhuast gasses pass through the turbine, which in turn spins the compressor creating pressure from the turbo. when you change gear the turbo is still spinning at high revs (up to 200,000 revs) when the engine is not (the turbo is indirect drive) and there is suddenly an extreme build up of pressure from the compressor, the turbo releases either the pressure or slows the turbine down to lower pressure, and it does this with a wastegate.

On your Peugoet the wastegate is operated by a build up of pressure on the inlet (compressor) side. When there is enough pressure build up the pressure is transfered through a pipe into an actuator, which in turn pushes a rod that then opens a valve on the exhuast (turbine) side.

The only way of checking it would be to take the turbo of the engine and see if it's seized or broken.

Hope this explains it well enough for you.

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Sat 28 May 2011 17:37
Peugeot 307 - Down on power, possibly Turbo waste gate? - unthrottled

when you change gear the turbo is still spinning at high revs (up to 200,000 revs) when the engine is not (the turbo is indirect drive) and there is suddenly an extreme build up of pressure from the compressor, the turbo releases either the pressure or slows the turbine down to lower pressure, and it does this with a wastegate.

Oh dear...

1.) The wastegate relieves pressure upstream of the turbine, not downstream of the compressor.

2.) You're describing the function of the diverter valve.

3.) Diesels don't have diverter valves because there is they use little or no air throttling.

OP-Ignore the twaddle above. is there an EML showing or fault showing up on the digital display?

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Sat 28 May 2011 17:39
Peugeot 307 - Down on power, possibly Turbo waste gate? - unthrottled

There are lots of threads on 'turbos not working'. The usual fault is to do with wastegate actuation (or lack thereof) leading to turbo overspeed.

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