I installed 373's in my 2007 GT/CS....along with the pre-loaded tune from Bama....on a cold start it jumps to 2000...down to 1500....and settles in at 800 all in about 6 seconds...not good for an engine.....any idea's?
99% of aftermarket tunes do the same thing. If you're accurate in your estimation of 6 seconds that's not bad. My 1st tune hung at 2,000 for 6 seconds before settling down to idle...... that was not acceptable.
When you say you installed 373's - you mean you installed a 3.73 rear axle gear in your car? Just curious. If so - you still have to reprogram the Ford PCM to acknowledge the different axle ratio. This can only be done with "IDS" - the Ford factory scantest platform. The aftermarket "tunes" only control so much. They dont completely override the PCM. The care is going to be "wierd" if you dont do this. If the situation exists were you need to reprogram your PCM - the aftermarket tune is going to get wiped out in the process unless your totally remove it.