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Hi,
Just taken my 1995 9K 2.0 LPT for a run along a country lane.
As i was changing gear I noticed a whooshing noise, very similar to a car with a wastegate, but mine doesn't have one.

I have checked all the hoses around the engine and turbo, suspecting a leak, but haven't found anything.

Is this normal?

It did sound quite good, maybe I will have to fit a wastegate to get it properly!!

Thanks in advance,
cheers
wayne
 

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I suspect your wastegate is stuck or the actuator rod connecting to the wastegate has come off; it is held with a spring-clip and a pin. First thing in the morning when car has not been driven and the engine cold, stick your hand between the exhaust manifold and the engine and see if the metal rod between the turbo and the actuator (silver round cup) is fixed or hanging loose....if fixed but you can not feel any movement along the axis, wastegate is stuck.....you need to gently tap the wastegate with a long rod and hammer to work loose. Try!
 

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The boost doesn't get released to the atmosphere, it gets fed back to the air duct before the turbocharger compressor via a recirculating dump valve. The whoosh you hear from some turbo cars comes from the non-recirculating type dump valve venting to the atmosphere.

Your type of dump valve doesn't normally make a very loud noise .On a standard LPT car it is normally audible only if you have a window wound down.

If you can hear it very clearly I would suspect that you are getting more than normal LPT boost or ' base boost'.

I had a problem with this a while ago, it turned out to be the small tube that feeds air from the compressor side of the turbo to the wastegate.
It had a hole in it and , as this was reducing the pressure at the wastegate, it stayed closed.This gave me more boost than normal. It felt great until the overboost fuel cutoff switch activated.
 
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