Marky2

Hi folks

Just wondered if anyone has had this problem before or what it could be. While driving my 98 impreza type R when I go through the gears the car hesitates and there is a large sound of air been sucked in and then released. There is no dump valve fitted but you would think with the sound that there was.

Ive had the car 6 months now and this noise has only started happening. The turbo sounds fine and the car is picking up which makes me think its not the turbo, but it might be an air leak?

However the car is not the same as when I first had her there is that lack or response now when you hit the throttle which wasnt there before.

Could it be an air leak or sensor? How or where would I start?

The car is very low milage and very well looked after and not abused so this is really annoying me as what like to get to the bottom of ma problem.

Thanks alot

Splitpin

Can you describe this to us in a little more detail? When exactly do you get the "sucking in" and "releasing" sounds? One when your foot is on the throttle, one when you lift off, some other time... what?

Clarification needed here. Do you mean that you (or someone else) has removed the standard fit dumpvalve, or do you mean that it's running the standard one (because you haven't fitted an aftermarket replacement)?

Most likely to be a leak but exactly where is the question. Tell us more about the nature of the noise and it should be clearer what's going on. Also, do you have a boost gauge? If so is the car maintaining target pressure?

In the absence of any further information, have a close look at the y-pipe that runs between turbo outlet and the intercooler. Make sure all the bolts and jubilee clips are still tight.

Also, on the assumption that you do actually have the standard fit dumpvalve in place, and assuming your "98" car is a version 4, find the DV, which should be under the intercooler, and make sure the recirculation pipe that connects to the turbo inlet hose is still connected both ends.

Beyond that, the more you tell us, the easier it is for us to help you.