I have a stock '98 GT. It has always run well although it recently developed a spark knock during quick acceration. It has the electronic ignition system (no cap or rotor) so I simply changed the plugs. The spec for plug gap is .052 to .056 so I set them all to .054. Once I changed the plugs and cranked it, it ran rough at first but then seemed to settle down. I took for a test drive and on quick acceration, it began to spit and sputter. I used NGK V-Power plugs as recommended by the dude at the parts place. He said that's what he uses in his Mustang. I double checked to make sure everything was connected and everything was tight. I don't know what to try next.

Any clues?

Thanks

 

well you allready checked all the wires for tightness correct? did you check to make sure you put he correct wires to each plug?