Tony172

As title really if I accelerate hard in first and go to change to second it feels as if the car looses power then comes back"

bludgod

iTrader: (3)

do you have a super kewl dumping valve to make 10hp between the gears? sometimes they can mess up and you'll lose power.

Tony172

Sorry I'm new to the Subaru world where would I find the dumpi vale fitted?

bludgod

iTrader: (3)

Take a picture of your engine bay and post it up - the dump valve will be attached to the big radiator thing under the bonnet scoop.

bludgod

iTrader: (3)

standard one looks like this:


aftermarket ones come in all shapes and sizes.

Tony172

Thanks guys basically mine has an elbow coming out of there with a hose and a bolt stuck in the end

Zuber

Sounds like a "Frankenstein" style valve you have there

Tony172

Haha thanks I now have a proper dump valve on order and going to try that

Mark89dawson

This sounds a little like my problem I have a hesitation type affair when I shift to second I've put a post up asking for any advice funny thing is I'm sure my dump valve doesn't always hiss when shifting!

Zuber

If your car still has the oe dump valve you will not really hear any noise while changing gear as its recirculating the charge air back into the system. But if you have an aftermarket panel filter and definitely a cone type induction kit it is more audible. Vent to atmosphere dump valves then you will get that whoosh sound with every gear change.

On that note the atmospheric valves will usually mess up the fuelling and makes the engine run lumpy so worth staying away from unless your running mega bhp on a race set up.

Mark89dawson

Yes it's a baileys chav valve I believe they can suck on the maf and cause it to run ritch?

bludgod

iTrader: (3)

They can leak as well which sucks.

As a test you could try blanking off the dump valve hole on the intercooler. Attack a coke tin with a pair of scissors and make a triangle shape. Slip it n between the dump valve and the intercooler and see if things improve.

Zuber

@bludgod what the hell are you going on about, going Blue Peter on empty coke cans,,,don't talk crap!! Op don't listen to that waffle and just fit an oe valve and see how things go!

bludgod

iTrader: (3)

@zuber - yes OK have him just lay down and squat out parts he doesn't have to hand - that makes loads of sense.

Did i say run like this all the time? no.
Did i say this was the mighty power mod to make 500 torques? no.

All I was saying was try it to blank off the dump valve if its leaking then this will stop it leaking and he'll know if it needs replaced.

Zuber

@bludgod What you say does not make any sense, if your looking for leaks on a piece of equipment you do not block off the energy source as you will never find the leak...Take the valve off, and check the diaphragm,spring and seals etc if you want to do it properly.

bludgod

iTrader: (3)

I agree with you there if you want to do it right take thing apart and also pressure test the system too. But if you have limited tools and time it might help narrow the source of the problem.

stevie turbo

iTrader: (12)

I totally agree with bludgod for diagnostic purposes this is correct, I have an oem one on and my 05 is down on power in lower Rev range...
I've tried every thing cleaning boost solenoid etc etc no luck.
When I first got car a PPP one it went like a stink put a vent to atmosphere as I personally like the chav sound i lost power big time so stuck with oem. I'm a a mechanic 25 yrs experiances and I just done the coke can blank off sorry I mean Pepsi can lol it its a cheap quick way to diagnose and if it's an oem one you can't strip to inspect anyway....... And my drives better with it blanked so I need another one...

Tony172

Hi I have fitted an atmospheric dump valve and the problem has gone away some donut put a bolt in and blanched off the pipe