4stringMike

My car's developed a loud screeching sound when pulling away hard, and most times the engine is under heavy load (eg if I floor it in second at say, 30mph).

The noise seems to start at around the point I'd expect the turbo to have achieved maximum boost, and stays until you back off (it'll then do it again in the next gear)

At first I thought (dreaded) maybe the turbo bearings were dieing, but the other thing to note is that there doesnt seem to be any lack of power at all, the car still pulls hard, it just makes this terrible screeching sound.

I asked my mate who's had 3 scoobys what he thought and got him to listen to the noise, and he reckons its more of a whistle than a screech and suggested it might be an air leak somewhere between the turbo and the inlet manifold, which may be coming from a loose/split hose or possibly a knackered dump valve (which is stock).


The car is a bugeye WRX and is standard apart from the exhaust.


Anyone else experienced this and have any ideas what it could be?



Cheers,

Mike

CallumW

Tyres rubbing the inner wings?

Is the sound constant or does it vary in pitch?
What happens if you rev the car when it's in neutral - does it do it then?

c_maguire

I doubt you would hear a leak between turbo and inlet manifold that didn't affect the performance of the car. Sounds more like a leak at the exhaust gasket of the turbo or possibly between downpipe and centre section. I had a Seat Leon that sounded like a cat was being strangled under the bonnet when the turbo span up, as time passed the leak got worse and it sounded like your typical shagged 80's Escort.
Kevin

4stringMike

The sound is a constant pitch, and does not happen at all if you sit in neutral and rev it, like I said it only happens if the engine is under heavy load.

Most of the time I can drive it around and not make it happen, its only if I give it the beans that it makes the noise.


Oh, and it sounds more like a mouse being strangled and amplified through a PA system




Anyone else?

CallumW

take it to a garage - may be a transmiison issue.
Perhaps the Viscous Coupling or LSD slipping?

Dill_typeR

I had a similar problem the other day, i thought there was a noticeable lack of top end power, fine below 3.5k, although mechanic said it sounded ok and was pulling ok(although he'd never driven the car before so thats understandable)
He took it out for a spin on his own with a boost gauge then returned and found a split pipe from inlet manifold.

I know you said it feels like its pulling OK, but just check the small flex rubber pipe from your inlet manifold

4stringMike

Thanks for the replies.

I never considered a transmission problem. Will have to bear that in mind.

I think what I need to do is remove all the hoses that might be causing the problem, and check them for splits. At least that way theres a chance I'll find the problem, and have a cheap and easy solution to it.


If thats not it, does anyone in the Watford vicinity have a standard DV I might try out on my car to rule that out?


Cheers,


Mike