ENGINE MISFIRE! Hey maybe you guys will be able to help me with something. I have a 2000 impreza rs 2.5 with 110,000 miles on it. The car runs great minus the headgasket that I just had replaced and a brand new clutch. My problem is the throttle response. When I'm in third gear at about 4,500rpms my car feels like its holding back and then all of the sudden the power kicks in and it begins to accelerate like it should. It does this in 2nd, third and fourth gears. Please help if you can because this is a pain in my cula, I have already replaced the sparkplugs, had the engine checked, a hedgasket replaced and a new clutch all to no avail. Could it be the ECU chip?