A/C problems - 92 LS400
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A/C problems - 92 LS400
When I bought my LS400 about 2 months ago, the car had already been converted to R134a. The compressor was making a very slight grinding noise like the bearing was starting to wear out. The A/C always worked great on the highway at 45+mph, but around town it was just somewhat cool. I figured it was just low on refrigerant.
Fast forward to this weekend and I make a trip down to Florida. The A/C worked the entire way down, nice and cold. I even noticed in Florida traffic when I finally got there that the a/c was staying very cold and working really good. Well I park it over the weekend, then pick it up at the valet 2 days later to head home. I drive off for a few minutes and then put the A/C since I was on the highway and it would be nice and cool. No A/C! The compressor wasn't even turning on.
Got home last night and ran the A/C diagnostic codes as per lexls.com. Nothing shows up, just a 00 (indicating system should be fine?). After reading a few threads on here I decide to test if the compressor will even turn on. I got underneath the fuse box and pulled the MG Clutch relay and bridged the two copper terminals with a wire. The compressor immediately turns on, so it should just be low on refrigerant right? I put a gauge up to the low side of the A/C system and the pressure is at about 15psi. Great, hooked a can of R134a up to it and got the pressure up to a nice 35psi. A/C is still blowing warm! I can hear the compressor turn on everytime I turn on the A/C, but no cold air whatsoever, even at highway speeds.
Does anyone have any ideas what could be wrong? 95 degrees and no A/C sucks!
Fast forward to this weekend and I make a trip down to Florida. The A/C worked the entire way down, nice and cold. I even noticed in Florida traffic when I finally got there that the a/c was staying very cold and working really good. Well I park it over the weekend, then pick it up at the valet 2 days later to head home. I drive off for a few minutes and then put the A/C since I was on the highway and it would be nice and cool. No A/C! The compressor wasn't even turning on.
Got home last night and ran the A/C diagnostic codes as per lexls.com. Nothing shows up, just a 00 (indicating system should be fine?). After reading a few threads on here I decide to test if the compressor will even turn on. I got underneath the fuse box and pulled the MG Clutch relay and bridged the two copper terminals with a wire. The compressor immediately turns on, so it should just be low on refrigerant right? I put a gauge up to the low side of the A/C system and the pressure is at about 15psi. Great, hooked a can of R134a up to it and got the pressure up to a nice 35psi. A/C is still blowing warm! I can hear the compressor turn on everytime I turn on the A/C, but no cold air whatsoever, even at highway speeds.
Does anyone have any ideas what could be wrong? 95 degrees and no A/C sucks!
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LexiBanna1
LS - 1st and 2nd Gen (1990-2000)
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08-25-17 08:41 PM