I have this annoying misfire that comes and goes away and i cannot figure out, i tested the module underneath the coil packs, i have swapped the coil packs out with my spare ones, still does it, fixed the one wire that had an arcing problem at the boot, still does it, i changed the plugs also, still does it as well, i changed my fuel filter out and it still does it. I am really stumped on this one. Please help guys

 

most common things could be- vacuum leak in the intake manifold, throttle body or vacuum plumbing, a defective EGR valve that is leaking exhaust into the intake manifold, or even bad gas..
less common causes could be bad- spark plug wires, worn or fouled spark plugs, a weak ignition coil, dirty fuel injectors, low fuel pressure, or weak valve springs

 

Do you know which cylinder is mis-firing?

Some people recently had issues with the fuel regulator causing mis-fires. You may also have a failing injector. As msnyder1112 pointed out, could also be a vac leak.... With the car idling, mist starting fluid around all vacuum lines and connections, listen for the idle to change.

 

thanks for those ideas guys, i didn't even register to me that it could of been a vacuum leak, im also considering that it might my throttle body gasket

 

it was either the t section under the throttle bracket on top of the upper intake/plenum, but I also replaced the throttle body gasket, but the problem is gone and she is running like a champ and punching great. Thanks for the help guys