03gt Running Bad


New Member
Nov 13, 2013
Hey I need some help with my mustang, it stutters at idle and when under acceleration. It has a random loss of power when I step on the gas. At idle it make a random popping noise out the tail pipes like its misfiring. I could get a video if it helps.. Also if it helps I have a CAI, offroad x-pipe, and it's tuned..
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Clearing the codes doesn't ensure the problem is fixed. Sometimes the codes don't come back at all and the problem is still there. Fix up you misfire and see how it goes from there. It is most likely the problem.
Ok so i go to a automotive school right now and my instructor said that it didn't feel like it was a complete miss like it wasn't a spark problem and maybe an injector so I ran a fuel injection cleaner machine on my car to see if it helped but it didn't.. So then I got the codes for the Miss on cyl7 so i switched out the coil and plug onto a different cylinder to see if the stutter would move to that cylinder but it didn't change.. And I erased the code because someone that was working with me didn't know how to use a code reader and deleted everything.. But right before they did that on the way to the school on the freeway the check engine light started to flash.
A flashing check engine light is worse than a check engine light that stays illuminated. It usually means there is a problem that could result in severe engine damage or catastrophic failure. Tread carefully with the car. You don't want it to get worse and create a larger problem.
Actually, a flashing CEL is a dead give away that there is a miss. If you swapped the COPS and still no change on that cyl then check the boot and then the plug it self and make sure no coolant or water got down into the plug well.