Automotive Air Conditioning Information Forum

JohnHere wrote: Sun Aug 09, 2026 2:38 pm Incidently, what are the year, make, model, and engine size of your vehicle? I don't recall your mentioning those.

Does your vehicle have an under-hood decal showing the A/C specs? If so, post them here. If not, I'll see whether I have them.

1995 VW Golf GTI, 2.8L VR6

Sadly, the decal, if any, vanished with the crumpled-up hood when I got hit, a few years back... . I do have the Sanden sticker that was on the compressor...

But I've got the Bentley "Red Book", which has the specs (some of them, at least?) They show the oil distribution and amounts, at least (and the refrigerant *weight*, I think?) - are those what you're thinking of?

Blowout wrote: Sat Aug 08, 2026 3:33 pm
(3) Bought a can of R134a and repressurized, but
(4)) when I disconnected the can of R134a, the Schraeder valve had apparently given up entirely, so the can ejected its entire contents right back out the low side valve.port (redolent of Mt. St. Helens blowing its top.)
(3) So, I replaced the Schraeder valve / cap assembly, and after checking to make sure it didn't leak down, like before, and
(4) I repressurized - this time adding a 3 oz. can of FAG oil to replace what I imagined had been blown out the low side port (BAD assumption...).

YMMV

I'm sorry, but this comment makes me think you used a low-side charging kit from the auto parts store after your Jiffy Lube visit. If you had used proper gauges. Then you would have both your low and high-side readings. Those Sanden compressors are tough compressors. Extremely odd to blow a hole in the case. One would really have to be doing a few things wrong to achieve that.

Flush the system: new compressor, condenser, receiver drier, and expansion device. Blow out the evap core and the hoses with nitrogen. Then add back the proper amount of oil, evacuate & recharge.

After a couple of cross-checks, both sources to which I have access say the same thing: 28 ounces net weight of R-134a, and 4.0 fluid ounces of PAG-46.

Tim wrote: Sun Aug 09, 2026 4:18 pm
I'm sorry, but this comment makes me think you used a low-side charging kit from the auto parts store after your Jiffy Lube visit. If you had used proper gauges. Then you would have both your low and high-side readings.

Yeah - that's the basic scenario... But, like I said, I thought the AC system was *empty*, after it evacuated itself through the low-side Schraeder port.

That reminds me... I've never been sure whether or not the "high side" is able to depressurize through the "low side", with the engine not running. I.e., will it "leak down" while the car is left sitting, or does it hold pressure?

Tim wrote: Sun Aug 09, 2026 4:18 pm Those Sanden compressors are tough compressors. Extremely odd to blow a hole in the case. One would really have to be doing a few things wrong to achieve that.

That's what I thought too - as I mentioned above, "how the **** can THAT happen". It seemed to me it would take some kind of detonation - dieseling, of some sort? to build up *that* much pressure. And how could it produce such a relatively small hole?

Tim wrote: Sun Aug 09, 2026 4:18 pm Flush the system: new compressor, condenser, receiver drier, and expansion device. Blow out the evap core and the hoses with nitrogen. Then add back the proper amount of oil, evacuate & recharge.

Oh, yes... apparently that's "the only way to be sure"...

JohnHere wrote: Sun Aug 09, 2026 4:40 pm After a couple of cross-checks, both sources to which I have access say the same thing: 28 ounces net weight of R-134a, and 4.0 fluid ounces of PAG-46.

That's pretty much what I got from Bentley... 30 oz. R134a, 3.9 oz. of lube...
In fact, now that I remember it, I was worrying about NOT having enough R134a, bc the can of Joy Juice from O'Reilly was only 28 oz. ...

Thanks for all your help -