a/c question
Thread Starter
Burning Brakes
Joined: Aug 2002
Posts: 1,190
Likes: 56
From: Milan Indiana
a/c question
My 92 has had the plug for the A/C compressor un plugged for quite some time( maybe years with prior owner.) I've left it that way until this week. Put plug together and turned on and engine stalled. Once in garage and once today while driving about 35mph. If compressor is locked up will this be a result? if so what is the fix? Cant see it myself so certainly need a second st of eyes to see what happens under hood. Any ideas? Thanks
Melting Slicks
Joined: Jan 2014
Posts: 2,176
Likes: 378
From: Lunenburg MA
I'm guessing you can't turn the compressor by hand? If the compressor is locked and the clutch engages, either the engine will stall or the belt will slip. A replacement compressor, system flush, and probably a new condenser would be the repair.
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
The compressor (shaft) is inside the outer pulley. You should be able to turn it by hand freely.
Thread Starter
Burning Brakes
Joined: Aug 2002
Posts: 1,190
Likes: 56
From: Milan Indiana
Thread Starter
Burning Brakes
Joined: Aug 2002
Posts: 1,190
Likes: 56
From: Milan Indiana
A/c
checked for codes- none checked connections all appear ok. Started car up ( takes awhile to warm up) and while feathering the gas to keep the rpm's up, turned A/C on auto and it works with cold air but car runs rough and if I take my foot from the accelerator, it dies Puzzled as I've read and watched video's but none seem to address this. I guess if I am running on the interstate at 70, it will work ok!!! any ideas before I go the dreaded dealer????
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
checked for codes- none checked connections all appear ok. Started car up ( takes awhile to warm up) and while feathering the gas to keep the rpm's up, turned A/C on auto and it works with cold air but car runs rough and if I take my foot from the accelerator, it dies Puzzled as I've read and watched video's but none seem to address this. I guess if I am running on the interstate at 70, it will work ok!!! any ideas before I go the dreaded dealer????
You have a engine that won't idle correctly and seems to run poorly. There is certainly basic items on the list that can cause poor idle. Plugs, wires, vacuum leak, IAC motor, dirty throttle body and idle set screw just to name a few.
You may just need a basic tune up for starters and go from there.
Thread Starter
Burning Brakes
Joined: Aug 2002
Posts: 1,190
Likes: 56
From: Milan Indiana
No not explaining myself evidently The supercharged engine runs perfectly- no issues at all. The a/c compressor was disconnected by prior owner . I plugged it back in and with car running i switch on the a/c and car dies. Pulley is free wheeling and if I feather the accelerator and increase the rpms the a/c works but car runs very rough. Let rpms go down and engine stalls. Turn a/c off, start car and it runs great. No tune up issue Spoke with prior owner and he just pulled plug on a/c as he didnt use it- sees no reason why it shouldnt work. When a/c works,the air is cold/ fan works great Thats why I'm puzzled. Can compressor go bad from not being used for several years? no appearance of leak and if there were a fuse bad, it wouldnt't run or cool I assume
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
The actual compressor will not go bad from sitting but what could happen is the seals can go bad especially front seal from not having any lubrication or movement. But if there is no leaks, then you should be fine.
Normally when A/C is turned on the ECM will send a signal to the IAC and increase the idle speed due to increased load. Since hearing that your supercharged, was a new tune performed?It may be part of the answer to the problem (just a guess). Maybe the IAC is not functioning properly.
Normally when A/C is turned on the ECM will send a signal to the IAC and increase the idle speed due to increased load. Since hearing that your supercharged, was a new tune performed?It may be part of the answer to the problem (just a guess). Maybe the IAC is not functioning properly.
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Thread Starter
Burning Brakes
Joined: Aug 2002
Posts: 1,190
Likes: 56
From: Milan Indiana
The actual compressor will not go bad from sitting but what could happen is the seals can go bad especially front seal from not having any lubrication or movement. But if there is no leaks, then you should be fine.
Normally when A/C is turned on the ECM will send a signal to the IAC and increase the idle speed due to increased load. Since hearing that your supercharged, was a new tune performed?It may be part of the answer to the problem (just a guess). Maybe the IAC is not functioning properly.
Normally when A/C is turned on the ECM will send a signal to the IAC and increase the idle speed due to increased load. Since hearing that your supercharged, was a new tune performed?It may be part of the answer to the problem (just a guess). Maybe the IAC is not functioning properly.
Advanced
Joined: Oct 2017
Posts: 53
Likes: 4
From: Farmville Virginia
How well do you know the guy you bought it from? Just a guess but sounds like to me he was having trouble with the A/C and unplugged it so it would run smooth while trying to sell it. Doesn't make sense to unplug your A/C just because you never use it...
Intermediate
Joined: Feb 2019
Posts: 33
Likes: 2
I have the same year and this same issue except everything is new..A/C system down to the ProCharger. Engine stalls at idle when the A/C is turned on. Running down the Highway when you turn it on really bogs the engine down and the engine heats up to the point where I feel I should shut the A/C off to bring the temperature down. What is the IAC?
Note: the A/C was disabled when I got the car. Condenser was removed. What's going on?
Note: the A/C was disabled when I got the car. Condenser was removed. What's going on?
Last edited by sheppard1; Aug 12, 2019 at 02:22 PM.
Melting Slicks
Joined: Jan 2014
Posts: 2,176
Likes: 378
From: Lunenburg MA
I have the same year and this same issue except everything is new..A/C system down to the ProCharger. Engine stalls at idle when the A/C is turned on. Running down the Highway when you turn it on really bogs the engine down and the engine heats up to the point where I feel I should shut the A/C off to bring the temperature down. What is the IAC?
Note: the A/C was disabled when I got the car. Condenser was removed. What's going on?
Note: the A/C was disabled when I got the car. Condenser was removed. What's going on?
Race Director
Joined: Jan 2012
Posts: 17,062
Likes: 166
From: United States
I have the same year and this same issue except everything is new..A/C system down to the ProCharger. Engine stalls at idle when the A/C is turned on. Running down the Highway when you turn it on really bogs the engine down and the engine heats up to the point where I feel I should shut the A/C off to bring the temperature down. What is the IAC?
Note: the A/C was disabled when I got the car. Condenser was removed. What's going on?
Note: the A/C was disabled when I got the car. Condenser was removed. What's going on?
Intermediate
Joined: Feb 2019
Posts: 33
Likes: 2
I was told by the mechanic that worked on the car that the IAC didn't work with the FAST ECM system and wasn't needed. He just adjusted the idle until it sounded good. I had the car timed by a reputable shop but this issue still exists. The compressor is again new but I'm not sure about the charge. The old IAC is still in the throttle body and hooked up. Should I disconnect it?
Race Director
Joined: Jan 2012
Posts: 17,062
Likes: 166
From: United States
I was told by the mechanic that worked on the car that the IAC didn't work with the FAST ECM system and wasn't needed. He just adjusted the idle until it sounded good. I had the car timed by a reputable shop but this issue still exists. The compressor is again new but I'm not sure about the charge. The old IAC is still in the throttle body and hooked up. Should I disconnect it?
I would as the company FAST if IAC can or can not be used. I bet it is used.
Intermediate
Joined: Feb 2019
Posts: 33
Likes: 2
I was thinking maybe it was because I have a ProCharger that it may not work? I dunno. Still waiting for the new IAC.