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Revisiting A/C again

2K views 30 replies 5 participants last post by  lowesguy 
#1 ·
Howdy everyone! again I will be working on my son's A/C,thought all was well but he tells me the A/C is not cold,so looking for a leak and pretty sure I found it,I ran my fingers under the expansion valve and lots of compressor oil there, last year I replaced evaporator, Expansion valve,and receiver drier.

I asked sonny boy how long did it last,he said I don't know? he does not use the A/C because he wants to save on gasoline? my wife rode in the car and told me its non-opt.

Looking at the Expansion valve it looks a little crooked and the input lines are not going into it straight,so O rings failed,my bad!:eek I remember it was a bitch getting in there,just no room,so this time I will pull all the trim above it for better access.
I tested the shrader valve on low pressure side and still has a little pressure in system,question I have is should I replace receiver drier? it was new last summer and system was not used.
Thanks!
 
#2 ·
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Looking at the Expansion valve it looks a little crooked and the input lines are not going into it straight,so O rings failed,my bad!:eek I remember it was a bitch getting in there,just no room,so this time I will pull all the trim above it for better access.
I tested the shrader valve on low pressure side and still has a little pressure in system,question I have is should I replace receiver drier? it was new last summer and system was not used.
Thanks!
John, just an idea here but how about just getting the BEHR evap core instead of that ACM thing that you had to bend to fit into place.

I think you created a stress point which then turned into a leak.

In other words, If it don't fit, don't make it fit. Just another example of why 3rd party can also be 3rd rate.

As far as the receiver/dryer, general A/C 101 theory is that the dryer should always be replaced whenever the system is opened up. The dryer is a low cost item.
 
#4 · (Edited)
Yea that cheap core is BS,should have left the original in, will work on it Sat, I do have a extra new RD from Autohauz ,will install it to.
No, since you already had to do open heart surgery to replace the heater core. But considering what a bear of a job this is you should have bucked up and paid up to get a BEHR (or OE MB) all aluminum core OR just let Sonny sweat it out a bit during those mild Temecula summermonths. :wink

Heck he doesn't even use A/C, so when he does ask for cold air just give him the father talk " . . . . when I was your age we didn't have fancy A/C and that's the way we liked it . . . and we all turned out OK . . . for the most part" :laugh:laugh:laugh

The evap core is just not a item where you want to think like the US government and award the contract to the lowest bidder. After all, it is your money, blood, sweat and beers.
 
#7 ·
Having a problem now? vacuum held for 6 hrs,so I put some UV leak dye and put in 2 12oz cans of R12 in, low side is at about 80psi and high side same thing but compressor is not kicking in at all? checked strip fuse ,its fine,jumpered the pressure switch on receiver dryer ,still no compressor engagement .
whats going on here? I think this system takes 2.5 cans of refrigerant,but should work with 2 cans in the system,have a 3rd can but pretty sure it wont suck it in without compressor working.
Ideas?
 
#13 ·
found KLIMA pretty sure its in the mass module,this is a 1992 car, not sure what to test on it? but one strange thing I found is heater not working at all or A/C? blower fine, so thinking CCU,will swap it out with old one ,see if system wakes up!:grin
 
#16 ·
Well getting better! switch CCU and compressor came on! both aux fans working now, can see refrigerant flowing thru receiver drier sight glass,have cold air at vents.
strange thing now is if I turn heater on,get heat but a/c compressor on also???? WTF!:eek
 
#17 ·
The push button CCU I bought last year was a re manufactured one,forgot what I paid for it? was working ok now its bad? I read somewhere if the aux water pump for heater go's bad,that can burn out the CCU,may be an issue on this car,can I just disconnect that pump for now?
 
#23 ·
I still don't think that's normal,only in defrost mode should the a/c come on, in reg heat mode,I can feel cold a/c air at center vents.and see freon flowing at receiver drier,reading other posts that suggest bad Mass module, I may just install shut off switch for a/c while in heat only mode, just not into spending $300 on it right now,engine runs flawlessly.
 
#21 ·
the heater is run with the AC in Defroster mode, but otherwise, the heat should only be heating if the temp setting is higher than the actual cabin temp. the AC does run on/off/on/off if its in normal or 'full' (up/down) and the temps are fairly balanced, the AC is off in economy.
 
#22 ·
Thanks for the info, I was aware of the a/c defrost mode and now on-off heater in reg a/c mode,still blows my my mind the re-manufactured CCU circuitry was taken out by something? researching theses strange issues,I found at least 10 posts across the internet and various forums about bad aux pump ruining the CCU.
Some suggest putting a 1amp fuse inline on the pump to protect the CCU.
 
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