e-man

Hey guys. 99 GS4 with 148k miles.

Last summer around June, my compressor went out. I found a used replacement compressor on CL from a 00 GS4 with around 60k miles. I took out the old, put in the new, and it blew ice cold for the rest of the summer and into the fall.

Obviously, I didn't use it during the winter. We're finally getting into some warmer weather in Chicago, and now the a/c is blowing warm again.

Is it possible that the compressor went out again? Do these systems lose freon? I know when the shop took out the old and put in the new, they did not bleed or recharge the system. Is it possible that the system had just enough freon to get me through the summer but that was it? I'm hoping I just need a simple system recharge, but I'm afraid it might be something more serious.

If anyone has any ideas, I'd love to hear them. Thanks for your help.

e

BichoteGS

gotta start by putting the gauges and checking the pressure in the a/c system. it is possible you have a leak somewhere. possibly evaporator. add freon with dye to the proper pressure and check the a/c make sure it blows and the a/c compressor clutch engages.if you do have freon and a/c not blowing cold and the compressor not kicking on the check the magnetic clutch relay. if thats good. than compressor is the bad guy lol hope this helps

phillygs3

iTrader: (5)

a/c system should never need a charge unless you have a leak

BichoteGS

it is normal to lose a small amount over a long period of time. especially if not used for long periods of times

ydjy

Is it possible to replace the compressor without evacuating and recharging the system?

Spyder78

iTrader: (7)

I dont think so, when my compressor was replaced they evacuated first.

BichoteGS

nope not possible.as soon as you loosen up the a/c lines on the compresor the freon will leak out. meaning you will have to vacuum and recharge new compressor

dcz

I just replaced my compressor this past weekend. Whenever you replace a compressor you should always replace your drier, too. It just so happens that our drier is connected to our condensers. When you changed your comp, they have to evacuate the system. You should flush your system when you replace your comp. Your comp always fails for a reason. Usually when it fails, it will shoot metal shavings into your system... these shavings will stay in the system and accumulate and ruin another compressor in a heartbeat. Also, if you do not replace your condesner/drier, the shavings can move from there to your compressor. In short, you may have already fried your new compressor. I know a local shop replaced 3 compressors on a toyota before (without replacing the drier) and that was what the problem was. Hopefully it isnt anything that serious. It could definitely be that its too low on freon. Like I previously said, go buy a recharge kit at a local parts store and get the reading. If you have access to a good set of gauges (High and low pressure) hook both of those up and crank up your car and get the readings (your car should have the AC on high and as cold as it can get). Watch it for several minutes and see what it says. I can help you out from there.

JeffTsai

iTrader: (1)

Seems like a lot of people are replacing compressors recently. This is not something that goes out very often on these cars.

e-man

Hey guys. Thanks for all the responses. Here's an update.

I took the car to Lexus today. They said the freon was low and they believe there's a leak in the system. They recharged the freon and used a "sniffer" to look for the leak. They couldn't find it, so they added dye and told me to come back in a week.

Here's the weird part. So you know how all GS400s have the low idle problem? Well, my car is no exception. I run my climate control year round. When the temperature is above 32 degrees, and I come to a stop in drive, the RPMs stay around 600. However, if the outside temperature is below 32 degrees, my compressor turns off, and when I come to a stop in drive, the RPMs drop to around 400 and the car shakes slightly. This has been going on since the day I got the car 5 years ago.

Well, today when I left the dealership, it was about 45 degrees out, so the compressor should have remained on at all times. As I was driving back to work, when I came to a stop in drive, the RPMs dropped to 400 (indicating that the compressor was not on). This happened several times throughout the day.

I called the dealership and they said it sounded "normal" to them. Well, like I said, I've had the car for 5 years, so I know what is normal, and this was definitely not normal. They said there is nothing they would have done today that would make the compressor perform differently than before I brought the car in. They said the compressor seemed to be working just fine.

Does anyone have any ideas? Why would the compressor be behaving differently now after the freon recharge? Shouldn't it kick on and off exactly as it did before? By the way, while it wasn't blowing cold for the past few days, I did not have the low idle problem.

Another poster mentioned something about the magnetic relay. Could that be the issue now? Any other ideas? Thanks again for all the help.

e

sakataj

iTrader: (182)

yeah, i noticed this myself....this isnt a item that is prone to failure guys. although jeff i have said that MOST mechanics instantly blame compressors as the problem to all air issues.....after of course blaming it on low or leaked freon

the sniffer u mentioned is just a freon leak detector.....so they installed a dye pack and told u to wait a week? dye doesn't take a week to circulate... wth? i will say this one thing OP if u "low" on freon STOP turning on the compressor before you do burn it out......or does our car have something similar to what we run in commercial refrigeration units...a low pressure sensor.i have done VERY little HVAC work on our cars so im not 100% sure but i thought they were kinda standard now-a-days on cars

lostthumb

I do not know if this relates but when I had my Expedition, my compressor died also. A mechanic evacuated the system and changed the compressor out for a brand new one. it worked for a while but then I was having issues with it not cooling at a complete stop. I took it back and apparently the new compressor was bad also. The mechanic looked into out and suggested that the initial evacuation was not good enough and the lines still had gunk in it. When a compressor goes out, large amounts contaminants and metal are discharged from the compressor to the lines of the A/C system. The mechanic did another evacuation and changed the compressor out. After that, my expedition was cooling correctly. Hope that helps.

sakataj

iTrader: (182)

......any good HVAC mechanic (not just a mechanic i mean someone who knows HVAC) should know to flush the lines before/after replacing the compressor so something like that doesn't happen.
although unless the compressor blows up it shouldnt leave bits of metal in it....although it can leave something most of you would refer to as "sludge" (its more like gummed up freon, possibly dye if they used this) in the lines

GS4_Fiend

iTrader: (22)

How do you flush the A/C lines?

e-man

Yeah, they told me to come back next week (so maybe not a full week, but at least a few days).

I keep coming back to the same question. If all they did was recharge the freon, what would cause the compressor to act erratically now? Whereas before it was always on above 32 degrees and always off below 32 degrees, now it seems to be turning on and off at random times. Again, the reason I know this is because of the low idle issue when I come to a stop at stoplights. When the compressor kicks on, it definitely blows cold, but it just keeps turning on and off (and the temperature here in Chicago today is around 50 degrees).

In terms of the original compressor, when it died, it died. It was making all kinds of knocking and grinding sounds. It wouldn't surprise me if shards of metal made their way into the system. When I replaced it last summer, I only replaced the compressor. I didn't replace the condensor or drier or any of the other parts. It sounds like if there was metal in the system, it could have destroyed the second compressor. However, once I replaced the compressor (June, 2009), it was fine all last summer and into the fall. Would it take that long for shards of metal to blow up a new compressor? I was under the impression that it would happen much more quickly.