hi lads.........................iv just put a dumpvalve on my classic wrx its not ticking over anymore anyone no why as soon as i take my boot off the peddle it just dies

 

Hello mate what dump valve have you got ? You have to make sure its a twin piston one as it opens up silghtly on idle to let in run. You only run single piston ones on cars with carbs on them.

jamie

 

yes its a single valve doh ..............thanks m8

 

I thought it was the single piston ones that are open slightly and thus cause the problem, the twin ones seal correctly at tick over and so idle sweetly?

On my brothers scooby (greddy already on the car) he has a single piston d/v and he has a slight tick over problem, this is cured by holding your hand over the outlet, surely showing that the single valve is not sealing and the air flow sensor is sending the wrong info to the ecu ?