94 LT1 A/C issues...
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Joined: Jun 2009
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From: San Diego CA
94 LT1 A/C issues...
Hi so after taking my car on a few road trips to the dessert this past month I used the A/C pretty much the whole time with no problems at all. All of a sudden a few days ago it just quit working all together. Air comes out of all the ducts just no more cold air.
anyone have any idea where I can start and find the problem?
Also as I was checking the fuses for the A/C i noticed both A/C fuse and A/C clutch fuses were missing, is this normal?
please help!
thank you!
anyone have any idea where I can start and find the problem?
Also as I was checking the fuses for the A/C i noticed both A/C fuse and A/C clutch fuses were missing, is this normal?
please help!
thank you!
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Joined: Jun 2009
Posts: 87
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From: San Diego CA
Ok so after investigating a little more here are some other findings i have found:
1) With the car running on A/C turned on all the way i get normal temp air
2) after about 30 sec of the car first turning on the Fan will go on after A/C is switched on
3) the lower A/C aluminum hose running to the condenser does get cold
4) the top aluminum A/C coming from the condenser stays warm
5) there is also a little bit of air leaking from the main aluminum A/C pipe that runs into where the blower fan it
Anyone have any idea what could be going on here?
Could it be possible that the condenser is clogged?
1) With the car running on A/C turned on all the way i get normal temp air
2) after about 30 sec of the car first turning on the Fan will go on after A/C is switched on
3) the lower A/C aluminum hose running to the condenser does get cold
4) the top aluminum A/C coming from the condenser stays warm
5) there is also a little bit of air leaking from the main aluminum A/C pipe that runs into where the blower fan it
Anyone have any idea what could be going on here?
Could it be possible that the condenser is clogged?
Le Mans Master
Joined: Jan 2006
Posts: 5,621
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From: Orlando FL
So far I don’t see any reason for those fuses to be missing. The A/C clutch is for the clutch of the compressor and is fuse #18, 10 amp. Fuse #43, 5 amp is for the A/C programmer which controls almost all A/C related functions including the fan and vent control. I do not see how that fuse can be missing and you have fan and vent control, I don’t understand that.
But if you had these fuses installed 18 & 43, then you could check these items.
Several places to start on this problem. First check to see if the compressor is turning, or engages and then drops out right away. If not turning at all check the low pressure cycling switch. Check the seating of the connector to see if it is dirty or corroded. You can also jump out the connector and see if the compressor starts.
If you have the automatic C68 HVAC system, do you have any flashing LEDs?
But if you had these fuses installed 18 & 43, then you could check these items.
Several places to start on this problem. First check to see if the compressor is turning, or engages and then drops out right away. If not turning at all check the low pressure cycling switch. Check the seating of the connector to see if it is dirty or corroded. You can also jump out the connector and see if the compressor starts.
If you have the automatic C68 HVAC system, do you have any flashing LEDs?
Le Mans Master
Joined: Jan 2006
Posts: 5,621
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From: Orlando FL
I guess forget all I said in my first post. I'm not sure not exactly what is really happening.
So now if seems like the compressor is running, so forget about Freon and much of the electronics. All I can suggest now is to check the connector on the fan power module under the hood on top of the evaporator box.
Also check the 3 way vacuum check valve under the plastic cover right side of the engine. If the valve is broken or cracked it will affect your vents and air flow.
Top line is the Freon leaving the evaporator on the way to the compressor (to be compressed)
All being considered it does not sound like the vents are working. Check the vacuum lines.
So now if seems like the compressor is running, so forget about Freon and much of the electronics. All I can suggest now is to check the connector on the fan power module under the hood on top of the evaporator box.
Also check the 3 way vacuum check valve under the plastic cover right side of the engine. If the valve is broken or cracked it will affect your vents and air flow.
Top line is the Freon leaving the evaporator on the way to the compressor (to be compressed)
All being considered it does not sound like the vents are working. Check the vacuum lines.
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Joined: Jun 2009
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From: San Diego CA
I dont have the automatic C68 HVAC system on my car, not sure how to check for codes without that unit.
The compressor is turning and I can hear the clutch kick in.
The connectors are dirty but not corroded... cleaned all of them.
the fuses missing are the 5a AC MDL & 10a AC clutch but A/C has always worked without a problem before when they were missing....
The compressor is turning and I can hear the clutch kick in.
The connectors are dirty but not corroded... cleaned all of them.
the fuses missing are the 5a AC MDL & 10a AC clutch but A/C has always worked without a problem before when they were missing....
Thread Starter
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Joined: Jun 2009
Posts: 87
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From: San Diego CA
I guess forget all I said in my first post. I'm not sure not exactly what is really happening.
So now if seems like the compressor is running, so forget about Freon and much of the electronics. All I can suggest now is to check the connector on the fan power module under the hood on top of the evaporator box.
Also check the 3 way vacuum check valve under the plastic cover right side of the engine. If the valve is broken or cracked it will affect your vents and air flow.
Top line is the Freon leaving the evaporator on the way to the compressor (to be compressed)
All being considered it does not sound like the vents are working. Check the vacuum lines.
So now if seems like the compressor is running, so forget about Freon and much of the electronics. All I can suggest now is to check the connector on the fan power module under the hood on top of the evaporator box.
Also check the 3 way vacuum check valve under the plastic cover right side of the engine. If the valve is broken or cracked it will affect your vents and air flow.
Top line is the Freon leaving the evaporator on the way to the compressor (to be compressed)
All being considered it does not sound like the vents are working. Check the vacuum lines.
Actually a few months ago that 3 way vacuum check valve was completely corroded so i just spliced it all together with a T connector and smaller pieces of vacuum tubing. I wonder if that can be it?
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Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
Please get the fuse numbers. It looks like MDL is for the C68 system. So it's probably OK not to have it. Obviously you have a clutch fuse in there somewhere if the compressor is running. The problem is not there. With a fuse # I can give more info.
Check the vacuum items. Can't offer more solutions because I don’t really fully understand what the exact problem is.
Check the vacuum items. Can't offer more solutions because I don’t really fully understand what the exact problem is.
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Joined: Jun 2009
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From: San Diego CA
New findings:
I guess before the AC compressor was never turning on... I decided to jump the low pressure switch and immediately the AC compressor kicked in, I didnt leave it on long enough to see if cold air started to come out the vents however.
Does this just mean my Freon levels are to low thats why my AC quit working???
thanks for all the help and patience once again!
I guess before the AC compressor was never turning on... I decided to jump the low pressure switch and immediately the AC compressor kicked in, I didnt leave it on long enough to see if cold air started to come out the vents however.
Does this just mean my Freon levels are to low thats why my AC quit working???
thanks for all the help and patience once again!
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
A set of gauges would tell you if the Freon was low and that is how you would really know. However if you jump the cycling switch and it get icy cold, then the Freon is probably not low.
You might then try changing the cycling switch and see if that fixes the problem. Not sure if that switch is adjustable or not. Might try bumping the adjustment, might give you a clue.
Usually if the system was working good, and it then quit, it's probably not low Freon. A leak would give you poor cooling for a while and then the compressor would cycle off to quickly for any real cooling.
You might then try changing the cycling switch and see if that fixes the problem. Not sure if that switch is adjustable or not. Might try bumping the adjustment, might give you a clue.
Usually if the system was working good, and it then quit, it's probably not low Freon. A leak would give you poor cooling for a while and then the compressor would cycle off to quickly for any real cooling.
Thread Starter
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Joined: Jun 2009
Posts: 87
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From: San Diego CA
A set of gauges would tell you if the Freon was low and that is how you would really know. However if you jump the cycling switch and it get icy cold, then the Freon is probably not low.
You might then try changing the cycling switch and see if that fixes the problem. Not sure if that switch is adjustable or not. Might try bumping the adjustment, might give you a clue.
Usually if the system was working good, and it then quit, it's probably not low Freon. A leak would give you poor cooling for a while and then the compressor would cycle off to quickly for any real cooling.
You might then try changing the cycling switch and see if that fixes the problem. Not sure if that switch is adjustable or not. Might try bumping the adjustment, might give you a clue.
Usually if the system was working good, and it then quit, it's probably not low Freon. A leak would give you poor cooling for a while and then the compressor would cycle off to quickly for any real cooling.
I also think I found out how I lost so much freon, when I disconnected the coupler from the low pressure line the ball valve inside continued to leak freon, I messed with it using needle nose pliers until I couldnt hear anymore hissing but I still think its going to eventually leak all out again.
Would all I need is that metal/rubber section of hose to fix that ball valve???
thank you again for all the help!
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
High side pressure fitting is a ball valve and go bad a lot. The fitting can be replaced but the system has to be evacuated and then filled again and done properly. If the low pressure fitting is bad which is where you added the Freon, I think the whole line has to be replaced but not sure.
