93 AC Problem
Thread Starter
Heel & Toe
Joined: Dec 2019
Posts: 20
Likes: 4
From: Little River, SC
93 AC Problem
Hey all! My issue involves AC that only blows hot air. The weather is heating up and there will be more questions about this.
Isn't it helpful to keep everyone from guessing when I disclose in the post title the year C4 we are talking about?
I hope everyone is hunkered down and staying healthy with this Chinese virus running rampant.
Here's the story. AC acted normal last year with cold air at the vents consistently.
No cold air this spring, only hot air. I noticed that the AC clutch was not engaging. I did the diagnostic on the HVAC system and it shows 09 low freon. I added freon to the limit without overfilling. As I was adding, the AC compressor began cycling as normal, but has since quit. However, no cold air was coming from the vents. I jumped the low pressure sensor and caused the AC clutch to engage, but it is intermittent and won't always engage. I have checked the fuses in the panel on pass side, all good. I'm running out of ideas, possibly the low pressure sensor needs replacement. Suggestions and comments please.
Isn't it helpful to keep everyone from guessing when I disclose in the post title the year C4 we are talking about?
I hope everyone is hunkered down and staying healthy with this Chinese virus running rampant.
Here's the story. AC acted normal last year with cold air at the vents consistently.
No cold air this spring, only hot air. I noticed that the AC clutch was not engaging. I did the diagnostic on the HVAC system and it shows 09 low freon. I added freon to the limit without overfilling. As I was adding, the AC compressor began cycling as normal, but has since quit. However, no cold air was coming from the vents. I jumped the low pressure sensor and caused the AC clutch to engage, but it is intermittent and won't always engage. I have checked the fuses in the panel on pass side, all good. I'm running out of ideas, possibly the low pressure sensor needs replacement. Suggestions and comments please.
Pro
Joined: Aug 2019
Posts: 596
Likes: 146
From: Minford, Ohio
Unless someone converted it to R-134A it has R-12 which is very expensive. Without a set of gauges, there is no way to tell what the problem is. What kind did you put in it? If you bought one of those 12 oz cans at the parts store you probably bought R-134A and if you added it to R-12 you will have to have the shop drain and flush the entire system. If they have to do that you should go ahead and convert it to R-134a. No matter what you did without a set of gauges you can't fix it properly.
Thread Starter
Heel & Toe
Joined: Dec 2019
Posts: 20
Likes: 4
From: Little River, SC
Car was converted to R-134A several years ago. I'm sure that I have a small leak in the system. Ice cold before weather cooled down last fall and car was parked over the winter months.
Pro
Joined: Aug 2019
Posts: 596
Likes: 146
From: Minford, Ohio
Some leaks are so small you can recharge the system and it will work all summer, if your lucky this is what you have. But, you still need a gauge to fill it, having too much is just as bad as not having enough and without a gauge, you are just guessing. If you have a harbor freight store close by you can get a set of gauges a lot cheaper than taking it to a garage.
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Thread Starter
Heel & Toe
Joined: Dec 2019
Posts: 20
Likes: 4
From: Little River, SC
I'm thinking that will be the way to proceed. My gauge shows level of coolant to be spot on. I'm going to change out my compressor cycle switch and low pressure switch since they are original to the car.
Team Owner
Joined: Jul 2004
Posts: 28,432
Likes: 3,285
From: Hartford WI
Throw what parts? If you have a leak, you need to fix it. Soon as you open it up, I would change the receiver/dryer. If it has never been done and it is R12, I would, and did change the rubber lines to supposedly R134A rated hoses.
Team Owner
Joined: Jul 2004
Posts: 28,432
Likes: 3,285
From: Hartford WI
Some leaks are so small you can recharge the system and it will work all summer, if your lucky this is what you have. But, you still need a gauge to fill it, having too much is just as bad as not having enough and without a gauge, you are just guessing. If you have a harbor freight store close by you can get a set of gauges a lot cheaper than taking it to a garage.
