jacobmon

I just purchased a 2002 GT with 12k miles. I had a SCT 5500B chip in it. I know absolutely nothing about mustangs or performance chips so please be kind. Performance wise the car reacted and outperformed other mustangs I test drove. I could tell a differnce in torque and it would scratch the tires shifting into second gear but when I put my foot into it, there was a rattling noise, which sounded somewhat like a bad altenator bearing and when decelerating the car jerked (not real hard but noticable) a little between 30-25 mph. I took the car back to the Ford dealership. They removed the chip and said that the noise was the spark plugs and both the noise and tranny jerk was due to the chip. I miss the performance of the chip. I know it was not much but I can tell a distinct difference. I guess getting to the ? - what can I do to be able to use the chip? I don't have the $ to be hurting parts. Would a higher octane level help? Like I said, I really know nothing.....this is why I need your guys' help. Thanks a lot!

HaV

Higher octane would probably help. It sounds like your detonating. You probably need to go to a dyno tuner or send it to SCT with the mods you have on the car listed. It sounds like they have the timing advanced quite a bit or the a/f set a little leaner then it should be. Try a higher octane to see if it continues, but I would definatly try to look up a local dyno that does SCT programing. They will be able to tone it down a bit for you and you will still have more getup then a bone stock mustang.