Anyone have advice for a mystery A/C leak?

**Naaman** · 06-14-2013, 09:48 PM

Starting in 2011, my A/C system stopped blowing cold. In prepartion for a trip to AZ (from WA), I took it to the dealer to have it fixed. They said given my car's age (1998), it was probably going to have stay at the the shop a couple days, because it's never "just a leak" at that point. Anyway, they tested it, used the dye, let it run for 2 hours, etc, etc and the system held pressure.

A few months later (when I decided it was time to use the A/C again), I was lothe to discover it was not blowing cold. Took it to a new friend who works at the dealer here, he tested it, it held pressure, so he recharged it. Days later it was not cold anymore.

Some time later, I took it to school and worked on it with my teacher. We drained it, filled it with nitrogen; it held pressure. We filled it with dye. No leak. We used soapy water... no bubbles. We even used the little sniffer thingie. No leak. We replaced the low side Schroeder valve and over charged it to 2.1 lbs. Tested it. It blew 41 degrees with an ambient temp of 71.

Held pressure for a few months... and then blew ambient air. Took it back to my friend at the dealer, and we went through it together in his stall. We could not find any leaks. We replaced the high side valve. Held pressure (as usual). After about a week, maybe a week and a half, it's blowing hot (ambient Phoenix summer air) again.

I'm wondering what to do next... Anyone have some experience with anything like this?

Help greatly appreciated.

**JayTA98** · 06-16-2013, 07:12 AM

so everytime it blew ambient air it was checked with the pressure gauges and it showed that it was low on gas? Was the compressor running not running?

**2002ssslp** · 06-16-2013, 05:50 PM

It's likely a leak from under the dash. Not a fun or cheap job.

**Naaman** · 06-17-2013, 12:37 AM

Compressor still works.

Interesting about it being a leak from under the dash. Even still, the leak would have to be amazingly slow to not register on the gagues, no? The system as a whole is supposed to be sealed.

**2002ssslp** · 06-17-2013, 05:24 AM

Originally Posted by Naaman

Compressor still works.

Interesting about it being a leak from under the dash. Even still, the leak would have to be amazingly slow to not register on the gagues, no? The system as a whole is supposed to be sealed.

May just be a pin hole. That's all it takes

**JayTA98** · 06-18-2013, 01:29 PM

yup it could be a pin hole like the other members suggested. you will not see a drop in pressure with a small hole like that. If is not an easy job to replace the evaporator inside the dash. are you checking around the orings?

**cammed goat** · 06-18-2013, 06:44 PM

^^this. We had a Kenworth dump truck come to our shop for a recharge a few weeks ago. Came back yesterday for another recharge. My coworker had to change the O-rings.

**Naaman** · 06-18-2013, 07:53 PM

O-rings, huh. Any idea how many O-rings are in our system? I have a 98.

For those who do this for a living: if it were your shop, how would yo determine if the job was a success? Just give it back to me and "wait and see"?

**JayTA98** · 06-19-2013, 03:08 AM

I did my compressor and replaced them all. I have an extra o ring kit. let me find it and I will post. I believe is around 7 o rings.

***SMWS6TA*** · 06-19-2013, 11:10 AM

have you tried the dye & florescent light yet?

**JayTA98** · 06-19-2013, 12:26 PM

Originally Posted by JayTA98

I did my compressor and replaced them all. I have an extra o ring kit. let me find it and I will post. I believe is around 7 o rings.

There are 7 aluminum o rings and a few rubber ones. You need the aluminum ones so I counted 7. They sell a kit for the whole a/c system for a specific vehicle. I think I pay like $10.

**jfl330** · 06-19-2013, 05:15 PM

Did you vacuum down the system each time before you recharged it?

Replace the o rings, lube the rubber ones with pag oil before installing. Rather than charging it, pull a vacuum on the system (as if you were recharging it) and drive it a while to see if it holds the vacuum. If a system can't hold vacuum for a hour, it has problems.

Jon

**Naaman** · 06-19-2013, 11:12 PM

Originally Posted by SMWS6TA

have you tried the dye & florescent light yet?

Yes. We even used the sniffer. I know that every time I worked on it, we fully vacuumed it each time.

***SMWS6TA*** · 06-20-2013, 09:38 AM

Did you check inside the car?

**ls1camino** · 06-20-2013, 10:02 AM

Time for an AC Delete

RACECAR!!!!

***SMWS6TA*** · 06-20-2013, 11:49 AM

Not in AZ......too damn hot in summer

**Naaman** · 06-20-2013, 06:03 PM

You know I HAVE been tempted to just rip the system out of there... But then my wife won't ride in the car with me... :P

**ls1camino** · 06-20-2013, 08:22 PM

Originally Posted by SMWS6TA

Not in AZ......too damn hot in summer

Drive faster and don't be a vagina.

**98TransAmWs-6** · 06-21-2013, 02:34 PM

Originally Posted by ls1camino

Time for an AC Delete

RACECAR!!!!

This...No more AC issues lol.

Originally Posted by Naaman

You know I HAVE been tempted to just rip the system out of there... But then my wife won't ride in the car with me... :P

That's a problem? Jk But seriously I understand but mine rides with me still and I have no AC in mine.

**Naaman** · 06-21-2013, 08:13 PM

LOL! Yeah, she'd ride Oct-May, anyway... It's turning out that my engine noise may be something way more serious than I thought, so I'll likely be putting this on hold for a while. We'll see...