i have a n/a with gas research fitted, however i can't get it to idle on petrol right, well it idles good as soon as i start it. but then, with in 10 to 20 seconds it slowly creeps up to about 1500. it dose this regarles if the car is hot or cold. this in turn effects the gas as well. need help. just so u know i can have the idel screw all the way in and it will still idle high. what could it be

i am in no way an expert on the subject but maybe i would be looking for a vacuum leak somewhere in the intake path, possibly a hose clamp or the intake manifold gasket? just have a fiddle around mate, make sure everything is tight and secure and then if the problem is still there, at least you have ruled it out as a cause oh and have a look on the ecu and turn the screw more towards the low setting it could also be the throttle stop setting on the throttle body, just check it out

If the screw was turned all the way your car would stall. So that means the problem may lie in your throttle body or plenum.

well i had the car at the mechanic and he tested for any air leaks with a special spray and he said it was fine. also he cheaked the butterfly on the throtel body and that was fine to.

have you tried unplugging the aac valve plug? it may be all gummed up or something, if you unplug it i wouldnt be suprised if your car stalls shortly after due to the idle screw being in all the way, so let it out a bit then unplug it and see what happens, it should idle at about 650-700rpm without it connected and roughly 100rpm higher with it plugged in if there is some change when it is unplugged, remove the aac valve from your inlet manifold and tke it apart, sraying it with carby cleaner etc then put it back on and all should be sweet and also it could be the idle circuit on the gas throttle body, just have it checked out. good luck