Need a little A/C help -- 91 Q
Need a little A/C help -- 91 Q
I had a bad A/C clutch and replaced the entire compressor with a used unit that is known to be good. The car was converted by the previous owner to R-134, and the compressor was taken from an R-12 car.The compressor was drained, and installed with a couple ounces of the proper oil. I had it filled, the clutch engages, but nothing gets cold. The guy who did the work says it's holding pressure (no leaks), and it took 2lb 8oz which should be a full charge, but nothing.All the heater controls are working, as is the fan. The diverter flaps (or whatever) behind the dash seem to be working since it will switch from hot to less-than-hot, but it never actually gets cool.So, how does one begin to troubleshoot an air conditioning system? Taking it somewhere and just writing a check is not really an option for me.Thanks for any help.
Re: Need a little A/C help -- 91 Q (mudpie)
So, how does one begin to troubleshoot an air conditioning system? Taking it somewhere and just writing a check is not really an option for me.Thanks for any help.[/QUOTE]
In effect,that is exactly what you have just done-no proper diagnosis,just threw parts{compressor} at it in hopes it would solve your problem,now you get to start over with a proper full system diagnosis by a trained a/c specialist to find original problem,and hope your used compressor isnt part of it! basically you have already wasted time and money trying to do it cheap! pay once for proper repair,even an expensive one,is far cheaper than half assing it when it comes to a/c work
In effect,that is exactly what you have just done-no proper diagnosis,just threw parts{compressor} at it in hopes it would solve your problem,now you get to start over with a proper full system diagnosis by a trained a/c specialist to find original problem,and hope your used compressor isnt part of it! basically you have already wasted time and money trying to do it cheap! pay once for proper repair,even an expensive one,is far cheaper than half assing it when it comes to a/c work
Re: Need a little A/C help -- 91 Q (qship96)
I don't need a trained A/C specialist to tell me my compressor clutch is shot. It obviously needed replacing, and I replaced it. Beyond that, I could use a little help. I thought I might get that here. Instead I got a lecture. Thanks, I think.
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Q451990
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- Car: 1990 Q45 - 118K, 2022 Toyota 4 Runner, 2004 Frontier M/T - 108K, 2012 Xterra (Mom's), 2023 Rogue (Inlaws)
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What are your low and high side pressure readings? Is there any temperature drop (measured with a thermometer) between the ECON and AUTO settings?
Also, did you confirm why your old clutch wasn't engaging? The clutch is controlled by the ECU and has to have 3 or 4 parameters right before it will do so. The dual pressure switch has to see a pressure that's not too low or too high, the a/c evaporator temp. sensor must not indicate a freeze up, and (i think the Q has one) the compressor temp. sensor can't be showing that the compressor isn't overheated. So it's not just a matter of "i pressed the switch and the clutch doesn't engage so it must be the clutch" to diagnose modern a/c systems. And I'm not lecturing... just trying to find out what has been done so far - since I don't have all of the information.
Good luck!
Heath
Also, did you confirm why your old clutch wasn't engaging? The clutch is controlled by the ECU and has to have 3 or 4 parameters right before it will do so. The dual pressure switch has to see a pressure that's not too low or too high, the a/c evaporator temp. sensor must not indicate a freeze up, and (i think the Q has one) the compressor temp. sensor can't be showing that the compressor isn't overheated. So it's not just a matter of "i pressed the switch and the clutch doesn't engage so it must be the clutch" to diagnose modern a/c systems. And I'm not lecturing... just trying to find out what has been done so far - since I don't have all of the information.
Good luck!
Heath
Re: (Q451990)
I did not intend my post to be a lecture! reread it and look for the clues to effective,cost efficient ways to solve your problem correctly in the least amount of time!,its all in there