Ok my problem started happening after I had a problem with the ECU when it was shorted and keeping the fuel injectors open. I replaced the ECU and replaced the injectors. In the beginning I had no problem at all. Then I started to get problems on occasion with the cylinder misfiring. Now it happens often. It's the front middle cylinder doing it I know this because I pull the plugs on the coil packs and when I pull the others the idle gets extremely rough but when I pull the front center one no change in the rough idle. The car drives like absolute **** if you ever driven your car with one of the plugs on the coil packs unplugged and one 5 cylinders it's annoying. Any suggestions. I was thinking maybe coil pack went bad? All possible problems are open. Oh yeah this happens too, at one point I was only able to put Amoco gas for it to run well and when I put Mobil,Gulf,Exxon it ran like crap. But now I have Amoco and same results it runs crappy.

 

It's either a coil pack or a FI. Swap coils from one cylinder to the next and see if the problem follows the coil. If it does, replace the coil pack. If it doesn't, look at the fuel injector.

 

So you don't think the problem is due to a bad cylinder right? Or anything electrical maybe fuel filter? Well I dont think fuel filter because it would be just that 1 cylinder

 

i swapped the coils packs and same cylinder misfiring. So try the fuel injector?