new car, strange issues

[thomas91169]

whats up guys, just got the car tonight. 2002 black on black GT 5spd, bone stock.

when i was at the dealership, i tested everything out, and at that time the a/c worked fine, when it was turned on, rpm's dropped like normal cars would, and came back up.

then i drive it home, i had the a/c off windows down, etc.

get home, my dad checks the car out, likes it, goes and turns the a/c on and the car dies.

my "car guy" neighbor seems to think the idle needs to be raised, though its at about 700 and i think thats pretty normal for 4.6ers(since i also have a 94 tbird 4.6).

if i hold the throttle at 1000 and turn the a/c on, it drops down to around 200ish but pops back up to 700 once its fully engaged.

i believe it might be an engagement problem in the a/c clutch, like its way too hard or something. but thats me.

any suggestions? i really dont want to take my newest addition to satan for them to fix a 5$ thing and charge me 500 bucks.

btw im a previous dsmer, so im pretty good when it comes to repairs, and im good at doing things to cars(i laugh at turbo swaps).

 

[Dark Knight GT]

whats up guys, just got the car tonight. 2002 black on black GT 5spd, bone stock.

when i was at the dealership, i tested everything out, and at that time the a/c worked fine, when it was turned on, rpm's dropped like normal cars would, and came back up.

then i drive it home, i had the a/c off windows down, etc.

get home, my dad checks the car out, likes it, goes and turns the a/c on and the car dies.

my "car guy" neighbor seems to think the idle needs to be raised, though its at about 700 and i think thats pretty normal for 4.6ers(since i also have a 94 tbird 4.6).

if i hold the throttle at 1000 and turn the a/c on, it drops down to around 200ish but pops back up to 700 once its fully engaged.

i believe it might be an engagement problem in the a/c clutch, like its way too hard or something. but thats me.

any suggestions? i really dont want to take my newest addition to satan for them to fix a 5$ thing and charge me 500 bucks.

btw im a previous dsmer, so im pretty good when it comes to repairs, and im good at doing things to cars(i laugh at turbo swaps).

One thing that tends to cause stalling problems on 4.6ltr GT's is dirty IAC valves, though I don't think thats the case in your situation. However, its worth a shot, so I say clean the IAC and eliminate that from the equation. Also, is there a SES light comming on by any chance ?

I think there might be some sort of bad disengagement/engagement relay between the A/C and ECU. Or, it could be the alternator is going bad, and just isn't able to suppor the AC when it comes on in lower rpms, though I don't think it would cut out, it would just switch power relay to the battery and you would get the batter light on the dash panel. You sure this car is using the stock pulleys ?

 

[Kilgore Trout]

Clean MAF, clean or replace IAC, then reset PCM you should be good to go. Max cost of this is less than $75.

The idle is not easily adjustable on these cars, you don't just turn an idle set screw so tell your old school garage mechanic neighbor named Vern to stay away from yer stang.

Here's a great resource, you should read the entire website:
www.bullittarchive.com

Also, how many miles are on the car?

 

[thomas91169]

took it back to the place i got it, and i believe they fixed it for free. he took off the t/b and cleaned it, took the IAC and cleaned that.

there were no codes being thrown when he checked it(which figures, all of my other fords, when they dont run right, never throw codes either)

now when you turn the a/c on it only drops like 100rpm and comes right back up to 700ish.