airattack111

iTrader: (2)

If I start my car with the ac on, it will sometimes surge to 200-300 rpm then either die or work its way back up to normal idle range.

It's throwing 2 codes.

p0108 - high freq map sensor "map is plugged in with hose attached working fine...)
p0121- tps sensor prob (replaced with brand new tp sensor and still throwing this code)

ENG SEN fuse is fine. This usually only happens when I turn the ac on when the car is cold, the ac belt needs to be replaced. But does the surging and the codes have anything in common?

MUSTANGBRKR02

iTrader: (91)

The p121 probably has a pinched or broken wire near the connector from unplugging and plugging it back in.

But i would venture to say that the A/C files were probably not adjusted in the tune after you tuned it for the cam?!?

airattack111

iTrader: (2)

I got it tuned by futral motorsports. Say I'm driving at 50mph with the ac on, and I drop it in nuetral, the rpm's will hang around 1500rpm until I get to under 10mph. Is this normal? Sometimes when I drop it to nuetral, it will go straight to idle rpm.

MUSTANGBRKR02

iTrader: (91)

I would first fix above codes. Then if problem persists look at the A/C part of the tune.

airattack111

iTrader: (2)

I replaced the TPS sensor, and went into the hptuners settings and changed min/max map readings allowed from 1 ranging to 100 so it doesn't throw the code.

But I'm still having issues. Car will want to die, or car will want to rev unusually high. Tonight I was driving it and every time I throw it in neutral the rpm's would rise up to 1600, in gear it would still think idle is 1600 and the car would move without the pedal being pressed????

Car has professional tune on it from futral motorsports.

P0121 tps code was "fixed" with new tps sensor, but it still threw the code so i edited it.
I'm not sure if it will even be worth changing the map sensor for the p0108 code because it will still throw the code.

I'm not sure what the problem is...

MUSTANGBRKR02

iTrader: (91)

How was it fixed but still throwing the code?

Frost

iTrader: (45)

If the TPS does not read 0% AT 0%, you need to fix that before you blame the tune.

Mike454SS

iTrader: (4)

Throwing a new sensor at a car that is throwing a code, getting the code again, and throwing your hands in the air while saying "what the hell?" and then editing the PCM to not throw the code...is NOT fixing the problem.

You need to verify like Frost said, that the TB is fully closing and then you need to verify that the harness to the TPS sensor isn't damaged (you'll need to wiggle it around while probing the wires for continuity, look for damage to the insulation, look for kinks that could mean damaged copper inside of them, look for bent/damaged pins...lots to check). You also need to check grounds, make sure the PCM has a clean ground, because if it doesn't, then the sensors grounding through it don't either.

AFTER that, you need to restore the conditions for the TPS code in the PCM, and see if it still sets...because it should not, and whatever is causing it to set the code, is also most likely what is causing the RPM's to hang and misbehave on you.

You're taking a horrible approach to troubleshooting the problem with the car. Just because it has a professional tune in it, doesn't mean the tune is perfect...I'm not badmouthing any sponsors...but nobody is perfect...I bet Frost still tweaks the tune in his own car once in a while ...it's very possible that they tuned the car really well, and didn't ever even think to click the AC on and make sure the car still ran properly while blowing cold air...it's also very possible that you have an AC compressor problem, or an electrical issue with the clutch (that wiring is different for a reason )...

kenp

iTrader: (9)

Did Alan Futral tune it and then you immediately began having problems?