Car won't IDLE

My 03 GT with a 5 speed is having a little problem with the whole learning to idle thing..... I bought this car totaled and have put her back together almost from the ground up, I have rewired most if the car and rebuilt everything except for the motor. I had it running the other day and it ran perfect no misses bumps or bruises, I finally got her ready for the road test and when I started the car it just refused to idle. If I keep the r's up it runs fine and it runs out just fine no throttle hesitation to speak of and it will bounce off the limiter with out question but it just won't freakin idle. I know the MAF sensor will effect this but I wondering if there is anything else that could cause this problem, the car has 54k on it.

Vac line isnt hooked up?

I have checked the ones I know of the bad thing is they don't make a book for it yet so I don't know if I am missing a vac line some where. I am hoping it is just the MAF sensor going bad.

Factory service manual is in one of the stickys.

fo' sho it is all inclusive and it has pictures. feel free to download and save for reference.

Thanks guys I found the service manual it will come in handy although nothing is left on this car in a factory setting lol... Hell the wiring is my own creation no harnes need haha, and yes everything works although I had to rewire the fuel pump I somehow wired it hot and it ran when the car was on or off haha got that fixed today. I installed a cold air intake and the car seems to be idling but when I rev the motor is doesn't seem to catch itself on the down side until its to late and stalls so maybe its a throttle position sensor or something. Who knows gonna take it up and have it put on the computer and see whats up.

my car stalls rarely as well, i attributed it to the CAI and the lightened flywheel.

is your maf located in it's original position or did you put it at the end of the filter down in the fender.

THe MAF sensor is in its original position, I did the somple unplug and see test and the car will idle with out the ma pluged in and dies the second you plug it in so my guess is the maf is bad. Gonna have a buddy pop her on the puter to find out 100% and then I will order the part.

Well I got a new MAF sensor in the mail and installed it. It didn't fix the problem the car would idle a little bit but as soon as the a/c it turned on it dies. I have looked for vac leaks but can't find any I am lost still havnt had a chance to get it put on the puter yet that comes later today. Any ideas I am all ears.

if it dies when your AC turns on then you might want to look at your compressor ...it could be siezing up. Also make sure your idle set screw is set correct. At idle you should be anywhere between 700-1000 rpm. If your car regularly idles, or tries to idle at 500 or so, you may need to bump the idle set screw a little higher, it might also be the reason your car stalls when the AC kicks on because if it is already idleing low, the initial added strain of turining the AC compressor on might be enough to kill it.

Keep in mind this only applies if your car only runs junky when you are trying to idle, and runs fine if you gas it a little. If it hesitates all the time, and seems like it's missing fire when you are at like 2500 rpm, your problem isnt your idle set screw....and for that matter i'm not sure what else to try.

Yea I have adjusted the idle.. Right now the car idles fine and I can run the ac fine but as soon as i try to plug in the MAF sensor the car does not want to idle.. I am also going to look into the IAC (Idle Air Control) I hope its not bad hell they run 300 plus for this damn motor. Thanks for the thoughs I am still working on as for now I will just have to deal with the 10mpg I am getting.

you might check the computer as well, when the maf is unplugged it is going to run in limp mode, and when it is plugged in it is going to decide on how much fuel you are getting. that would explain why it wants to die and get horrible gas mileage is it is dumping fuel because something is wrong. Also maybe the harness to the maf might have some corrosion and the wires all the way back to the ECU. if they aren't reading accurately it isn't going to give you good readings.

Try reseting the ECU, diconect the battery and reconect. Start the car with evrything pluged in and see if it can teach itself how to idle corectly. hell its worth a shot.

Thanks for the input I don't know why I didnt try to reset the ecu before. I will give it a shot and let you know.

Well boys and girls I got my GT to idle and run right after many long nights in the garage trouble shooting.. I ended up having to replace my MAF sensor and my IAC..... I got lucky and found a freshly totaled 03 GT in my local boneyard and pulled both parts for 50 bucks which saved me about 500 and some change.. I can't believe they wan't 357 dollars for an IAC and 250 for the MAF my god they must have gold in them..