yoden

so I recently picked up a 2004 mustang gt that used to run in pro drag the car runs and drives great except for the fact if I mat the gas the RPMs will stop and make a loud pop at 4k rpm if use maybe 3/4th or 1/2 throttle it will rev all the way up too 7k I'm looking for some help with this I have a couple of ideas either it is the sparks but they were done around 6 months ago or the timing is off. another potential cause is the battery being loose I am getting a new hold down today but IDK how much it will help. it currently is running no MAF sensor as the wiring is set up for a charger I'm considering that could be a problem as well I am going to bring the car to have it tuned as soon as I install my new bbk intake but I just wanted to see if anyone here could tell me what's wrong so I could fix the problem and not make it my tuners problem. if you have any questions about the car feel free to ask I don't know everything about it but I know the top and bottom end of the motor are built. any help is appreciated thanks!

WhiteFoxGT

sounds like it has a 2step/launch control setup. its either part of the tune or a seperate unit (MSD box or WOTbox) look under hood or glovebox for a weird looking box with led lights. Did the car come with a hand held tuner? if its a 5spd look on clutch switch for a tapped wire

yoden

the car was dyno tuned and I never received a handheld tuner I haven't noticed anything weird under the hood after installing a new throttle body and I just checked the glove box there was nothing irregular. but when I looked under the clutch there were a couple of different boxes with lights and one sensor that moves when the clutch is pressed in (gray box 3rd photo)

Derf00

The box with lights and the adjustment is probably what Whitefoxgt was talking about. I know nothing about them or the clutch setup on 96-04GT but, I do know that part is not stock and neither are wires that are twisted in your third pic. That is all aftermarket.

WhiteFoxGT

unplug that box briefly and see what happens