AlanW

Anybody got this?

On my car it does it at around 6k revs with quick gearchanging when accelerating hard ie. full boost. What happens is that when the next gear is selected and clutch released the car has no power for about 1 second then the boost picks up and off it goes. It is much more noticeable in the lower gears a) due to speed limitations in higher gears and b)the ferociousness of the boost and its corresponding no boost point

Could it be the dump valve not working and causing the turbo to stall therefore taking all the inertia out of it?

Alan

Stealth

iTrader: (4)

I have no idea what this is but I get it as well, it only started to happen after my service by so called specialists changed everything they could lay there hands on .....

I'm in hte middle of finding the problem myself, I changed the air filter... took the crappy panel one they put in a put an induction kit in and that's not fixed the problem, I've ordered some Split fire leads on HKS plugs to see if that sorts the problem. I'll let you know what happens from there

bruce

iTrader: (5)

I get this as well on my MY97WRX, the dump Valve was changed a few months back due to the "blowing over the bottle top" noise, but the problem stayed. I would be very interested in any info on this problem also.

AlanW

Still no clue then?

Claudius

That usually happens on cars with increased boost with the OEM dump valve that cant get rid of the air quickly enough and that recirculates it. Get a VTA BOV (but not an SSQV HKS).

Claudius

In fact, when you lift off, the turbo blades almost stall and need that second you mention to get back spinning.

You can normally solve the problem by buying a good piston VTA BOV.

AlanW

Claudius
I've had this since the car was delivered new. I have not modified the boost, only a straight thro' exhaust. So do I have too muc boost or a crap dump valve?

Alan

Claudius

It could be for other reasons than the one I mentioned, but we had the very same problem on a friend's car with lots of boost.
Obviously, impossible to tell without seeing the car. It COULD be that you have more boost than the average scooby, but unless you measure it, you wont know.

Try to fit the BOV from a friend's car to see if the problem remains. If so, it's something else, if not, it's your BOV. They are very cheap parts known to malfunction sometimes from the beginning, sometimes from 5,000 miles or less, sometimes never...

Claudius

Just re-read your message. When you change the exhaust, the boost increases slightly.

GavinP

Alan,

What MY is your car ?

Early cars have smallish BOVs which could explain the problem (92-96).
Cars in 97/98 apparently had a bigger design but it was problematic.
Newer cars (MY99+) have the BOV mounted off the intercooler which fixed the capacity and reliability issues.

Thanks

Gavin

AlanW

Gav,
MY2000 had the problem from day 1 with standard exhaust, then with mid+rear box then with added de-cat D/P, now with ECUTEK driveability ECU. Which I might add is well worth the cash, better mid range and much smoother with no more hunting when cold

Alan