So, my kid broke down in his 2002 mustang gt last night with a car that was free revving and hanging at over 3k rpms. I couldn’t fix it in the dark so I towed it home. I removed the throttle body TPS, , IAC, and MAF and cleaned thoroughly. I replaced the TPS, IAC, and MAF before I found the real culprit. It was good that I did replace this stuff anyway cause the IAC had a sluggish piston and something was causing the car to be very touchy shifting into first causing bucking. The combination of the three fixes solved the bucking but not the idle
The real culprit was far simpler. The stupid idle screw that is in his 73 MM BBK throttlebody kept unscrewing towards the passenger side when the car was driving due to vibration. This raises the idle. So simple that it took me more than 5 hrs to figure out. After verifying all the other stuff to include vacuum lines weren’t the issue. I put some locktite on the screw and perfect. No more issues. Editted which way the idle screw was moving and took off the zip tie as locktite dried and now it’s perfect without it.
Mods: bama tune, BBK 73MM TB, Full SLP exhaust with LTH, off-road X with HF cats, UDPS, short throw shifter, and a few more goodies
The real culprit was far simpler. The stupid idle screw that is in his 73 MM BBK throttlebody kept unscrewing towards the passenger side when the car was driving due to vibration. This raises the idle. So simple that it took me more than 5 hrs to figure out. After verifying all the other stuff to include vacuum lines weren’t the issue. I put some locktite on the screw and perfect. No more issues. Editted which way the idle screw was moving and took off the zip tie as locktite dried and now it’s perfect without it.
Mods: bama tune, BBK 73MM TB, Full SLP exhaust with LTH, off-road X with HF cats, UDPS, short throw shifter, and a few more goodies
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