idle surge and WOT hesitation

[Porkchop-wrx]

i start up the car then for about 15 mins it has irratic idle between 1200 and 2000 then as the car warms up it levels off to normal idle. And another problem do not know if they are linked or not but on WOT i reach 4500rpm the car jerks pretty bad and it really doenst let me pass it. But on part throttle i can take it to red line... any suggestions...

mods are...
evo 3 manifold and o2 housing (ported)
Apexi down pipe and cat back
all the rest is stock

replaced fuel filter and wires.

 

[Porkchop-wrx]

ttt


no one has got a answer?

 

[crankbender]

It sounds like you possibly have a leak. During idle this leak causes the engine to get too much air and then idle high. The ECU sees this and cuts fuel. This is why the idle bounces up and down.

During WOT the intake is allowed to escape out the leak and cause you to hit fuel cut.

Do a leak check on the entire intake tract and see what you have.

 

[92redman]

I had similar problem, replaced the spark plugs and all was well. Have you checked your plugs lately?