I have a strange misfiring problem ever since I got the car when you bring it up to redline or past vtec engagement (5500) when you let off the gas and let it idle it misfires really badly but goes away almost exactly 30 seconds later. I recently put a turbo on it and replaced the injectors,plugs, plugwires, Dizzy, vtec solenoid and fuelpump. We got it on the dyno it still misfires after the pulls. The ecu is a new ecu now chipped and tuned with crome. It misfires real bad. Compression checked out 180,185,183,180. It has an aftermarket cam and the tuner said it might have something to with that I don't know what cam it is. I was thinking it could be the iacv but the tuner said that might not be it. Checked valve clearances they were all within spec except cylinder three wich was a little tight on the exhaust side. Any ideas on what it could be?

 

mine did that and had a bad idle air control valve try that