RSWilson

Hi To All Once Again,

I recently bought a UK MY99 Turbo Estate and I'm really impressed with it.

I'm quite new to scoobynet and folks have been great in helping me to become familier with the technical side of these cars.
As such, once again I bring a question to see if anyone else can help.

I recently fitted a dump valve (yeah I know...) but its the first ever serious turbo car I have ever had.

When I accelerate in a usual manor through the gears the car seems to pull & lull very slightly when its on boost. Its not violent or exessive but if you feel for it you do notice it.

I put my hand over the dump valve trumpet and I can feel a slight suction.
I would have thought the vacum wouldn't be able to be felt - am I wrong?
Surely if I can feel the suction the dump valve could be leaking boost pressure?
Can anyone please confirm that dump valves do or do not have some suction when at tick over?

Cheers
Richard

charlesk

Feeling suction at idle is not a good thing...
This means that your DV is not sealing off properly (at least when the car is idling-could mean that is leaking under boost too but not necessarilly...), which is bad for a car with an Air Flow Meter as your Impreza.
This will cause problems given enough time.
Which DV did you put on?
Suggest you revert to std, and see if it still has the same symptoms.

If you really want a DV then at least go for a good quality one, specifically make for the Impreza to avoid any problems.

RSWilson

I bought a TurboSX dump valve that is a proper fitment for the intercooler.
I just didn't know if "they all did that" - I will swap it back and see how it goes. It has a trumpet style opening that I can put my hand over and it has a definat suction. I wasn't sure if it was the crank-case suction or what.

I can adjust the valve I think if I remember the instruction correctly.

Cheers for the thoughts though.

Richard