A/C Problems.....please help.
Thread Starter
Instructor
Joined: Sep 2003
Posts: 182
Likes: 0
From: SAN DIEGO CA
A/C Problems.....please help.
When i turn on my a/c it stutters. My a/c light flashes, the engine pulses from what seems like an on and off draw of the a/c, and when i popped the hood i can see the a/c clutch engaging and disengaging on its own. Also the lines freeze up and i don't get any cold air blowing inside. My car is a 92 LT1 6 speed and i had the a/c clutch and compressor replaced last year,
Thanks
Thanks
Pro
Joined: Dec 2001
Posts: 634
Likes: 0
From: Oregon
Originally Posted by CRVETTE92
When i turn on my a/c it stutters. My a/c light flashes, the engine pulses from what seems like an on and off draw of the a/c, and when i popped the hood i can see the a/c clutch engaging and disengaging on its own. Also the lines freeze up and i don't get any cold air blowing inside. My car is a 92 LT1 6 speed and i had the a/c clutch and compressor replaced last year,
Thanks
Thanks
Could be your pressure switch too. Maybe the electrical connection came loose, check to make sure it's secure.
Do you get any air in the cockpit? Your blend door might not be closing. There's a hard line (on my 88 at least) that's around the right side of your distrib. cap. That supplys vaccum to your door(s) controllers. To that hard line was a rubber line that then connected to a small valve. That rubber was melted and fell apart. Not sure what it was resting on but it was hot enough to melt that rubber.
There's a section on how to test to see if your heater etc. doors are working as they should.
Sorry I can't tell you exactly what's wrong but the above is a small start.
Le Mans Master
Joined: Mar 2004
Posts: 8,700
Likes: 298
From: Ft. Lauderdale Fl
Go with the quick fix first....
When the main and the secondary lines freeze up it is usually a sign that you are low on freon (R134a). The clutch engages and disengages as it is attempting to shut down and it will if you loose any more R134a. You need to find out the source of the leak. That can be done by adding a dye to the R134a and see the leak.
Pro
Joined: Dec 2001
Posts: 634
Likes: 0
From: Oregon
Originally Posted by elefkow
When the main and the secondary lines freeze up it is usually a sign that you are low on freon (R134a). The clutch engages and disengages as it is attempting to shut down and it will if you loose any more R134a. You need to find out the source of the leak. That can be done by adding a dye to the R134a and see the leak.
If your system uses Freon 134a, look at your compressor and it will tell you how much of a freon charge the compressor uses and how much refrig. oil it needs too. You can buy 134a over the counter.
You can buy a charging kit for less than $20. Look for a kit that has a gauge so you can see how much freon you have and when to stop adding freon. R-134a is a low pressure freon and the gauges are setup in colors with green being the color your want to be in.
Most of your leaks will be at the large fittings on the passenger's side where the lines go into your evaporator (into that box near your blower motor and at the receiver that's between your engine and the radiator.
Burning Brakes
Joined: Feb 2004
Posts: 1,024
Likes: 0
From: Long Island New York
You say the compressor short cycles and the "lines" freeze? Was that a typo or are both lines actually freezing? If it is just the Large line, you definitely need some refrigerant, unless you live in a cold climate, in which case you may just be over-condensing. (fairly normal) If both lines are freezing, just be aware of the possibility that there is a restriction in your system, i.e. strainer, orifice, etc. If you add refrigerant and the problem does not go away, i would suspect a restriction
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Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Unless it's converted, '92 is R12. If you don't know, check the Accumulator for a "quick connect" fitting. Should be there if a proper conversion was done.
The small line or high side freezing up usually means it's restricted and it's cycling because enough gas can't get through the orifice to the evaporator for efficient operation. Sounds like the compressor may be slugging some liquid too or is straining under pressure and it may all ready be shedding metal. It could also be spitting out chunks of desiccant from the Accumulator particularly if it's the original or it wasn't swapped out on a conversion or when the compressor was replaced. Also, if the old compressor seized and the system wasn't flushed, enough metal was probably left in it to plug it up.
For your own safety, check the operating pressures by hooking up some gages (either buy some or have a shop check it out - last ad I saw was 29 Bucks at Pep Boys). Don't add any gas as you can blow it up or end up with liquid in the compressor which will definitely cause it to seize. I would keep the a/c off too until you can get it checked out.
The small line or high side freezing up usually means it's restricted and it's cycling because enough gas can't get through the orifice to the evaporator for efficient operation. Sounds like the compressor may be slugging some liquid too or is straining under pressure and it may all ready be shedding metal. It could also be spitting out chunks of desiccant from the Accumulator particularly if it's the original or it wasn't swapped out on a conversion or when the compressor was replaced. Also, if the old compressor seized and the system wasn't flushed, enough metal was probably left in it to plug it up.
For your own safety, check the operating pressures by hooking up some gages (either buy some or have a shop check it out - last ad I saw was 29 Bucks at Pep Boys). Don't add any gas as you can blow it up or end up with liquid in the compressor which will definitely cause it to seize. I would keep the a/c off too until you can get it checked out.
Pro
Joined: Dec 2001
Posts: 634
Likes: 0
From: Oregon
If it's the small line I'd take it into the shop that did the compressor and clutch replacement and have them look at it. You don't see the high pressure line freezing up that often, just the low pressure return line's frost line.
I was under the impression that it was an R-134a system.
Not easy trying to help when you can't see the system and don't know the full history either.
Good luck.
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