Engine Performance problem
1996 Pontiac Firebird 6 cyl Two Wheel Drive Manual 144000 miles
I have a 1996 Pontiac Firebird with a 3.8 and 5 speed transmission. I have had it hooked up to a diagnostic computer and it shows that cylinder #4 is misfiring badly when its under a load and while at idle. The other cylinders do misfire, but not very often. I have replaced the catalytic converter, MAP sensor, throttle position sensor, Idle air control, it has all new vacuum lines, new coil pack, plugs and wires. And it has a new EGR. Also installed a new fuel injector on cylinder #4 and it didnt do the trick. I dont know what else to do.