Hey all. My 1990 civic hatchback had working AC all last summer, and now it is not working for this summer. It's been converted to R134 and all O-rings were replaced last year. The problem I am having now is that I can charge the system and it will hold pressure just fine. However, once it gets to the proper amount of pressure to kick on the compressor, the gauge instantly goes to 0 psi the second the compressor comes on. I pulled out the valve on the back of the compressor and it seemed fine. Put a bolt in there for the heck of it just to eliminate it from the equasion and the car is still doing the same thing. What else could be bad that is causing this?? I put UV dye in the system and it is not coming out anywhere in the engine bay that I can see with the black light. There was a ton of dye at the back of the comressor, but if the valve is plugged, where can it be coming from?? I'm sort of new to AC systems so any help is much appreciated.

 

You need to check it with a sniffer.

 

I fix everything I own myself. I will never take a car I own to a shop, because honestly I don't trust them. I'd rather pay $300 to replace a few of the A/C components myself than pay a mechanic $300 to tell me it's broken.

That said, I have a freind who works at a shop and he MAY be able to let me hook it up to the A/C machine to check it out after hours, but I'd rather not have to beg him for the favor. It seems like it's the compressor itself but I just want some insight from people with A/C experience. Someones gotta have an idea of why it's happening.

 

Same here, that's how I accumulated all the tools needed to do a/c work. I bought my own sniffer from eBay I also bought a vacuum pump and gauge set after borrowing them from friends. I try to pay it forward and lend out my pump and gauges to some of my friends who need it. All the guys at work borrowed my pump before I finally needed it.

http://www.ebay.com/itm/TIF-5550A-RE...#ht_500wt_1156

 

"There was a ton of dye at the back of the compressor"

Could be that one of the seals for the line connection at the compressor has been compromised.
When the compressor kicks on, it just blows everything out.

 

did you replace the drier when you replaced the o-rings (had the system open)? Did you pull a vacuum before you re-charged it? Could be a restriction or a bad compressor.
Does the compressor immediately kick back off? Does the low side line get cold at all?

 

Was the system evacuated before charging? Are you using a gauge manifold set and not a crappy autozone single gauge for the lowside only? Did you weigh in the amount of oil or was it guessed? What was the system's history? Does this only go down to 0 psi while running, or does it literally all blow out never to be seen again?

Both condenser and radiator fans running? Are the shrouds in place?

If you are using a single gauge sold with the death kits, stop. It only reads the lowside which tells nothing about the condition of the system at all. And if it just reads 0 psi only while running and goes to normal when shut off, you're pulling a vacuum on the system and you have a restriction somewhere (clogged/blocked TXV is likely).

We need more information and backstory on your a/c system and how it was put together to help more. A/C systems are very touchy, so if you have a friend who is a professional or is familiar with auto A/C work, have him/her look at it.

 

my 91 sanden compressor leaked once through one of the 4 bolts that holds everything together. its on the very back of the compressor facing the passenger side. I opened up the compressor and added a pressure relief valve by drilling into the back of the compressor housing. i was messing around with hydrocarbon refrigerants at the time and may have added way too much but never had issues since. just be aware that freon can escape through those 4 bolts.