Pontiac Repair: 01 Grand Am SE 2.4L, noid light, injector pulse

Question
Im working on a 01 Grand Am SE 2.4l of my friends and literaly about to pull my hair out because of it....The engine will only rev. to between 1500 and 2000 rpms when it starts missing and stalls. Watching on my scanner when raised above idle the number 4 cylinder missfires terribly, but when reved to 2000, all four cylinders missfire. I have checked the plugs, they are fine.I swapped the coils from front to back, thinking that maybe the miss would move to another cylinder, but it didnt.I ohmed out the injector, that came out fine, i checked the timing, that was also fine. Fuel pressure ranges from 55 to 62 psi at all times. Any help or ides would be GREATLY appreciated!!!!!!

Answer
Hi Brandon:

I would check this use a noid light and make sure you have good injector pulse on #4. Check compression on all 4 cylinders they should be with in 10% from high to low. One other tyning with these engines is the coil housings go bad they start to cross fire in the coil houing. Usually you loose 2 cylindres when they go bad not just a single cyliner. those are a few things to look at . good luck :-)