1990 A/c Repair

[jrulmyr]

my 1990 LS - (I'm original owner) with 145K miles, is without A/C, which faded 2 years ago, but was Ok for a season with a recharge, but now no go. The dealer is not encouraging, with his "search for the leak, and then fix" approach, which sounds like it will likely go at least $1500. So I'm thinking of getting rid of it. But is there an approach that might make more economic sense? I drive it very little right now as I am in semi-retirement, and it is in excellent shape. Otherwise I am thinking of a used early 2000's LS430, or new Avalon, or see what comes out for 2006. I like the ES, but there's too much wind noise, and the new GS gives me too much road feel. (Unfortunately, I like that silent and smooth ride.) What do you think?

[obergc]

Are you happy with the car other than the a/c leak? If the answer is yes, then I would personally get the a/c fixed. They should be able to put in a dye that will pinpoint the leak using a black light. The cost of the repair would then depend on where the leak is. I don't see how they could possibly give you a cost of repair without knowing where the leak is. One member has stated that he has found more than one LS leaking freon at a smashed "O" ring near the evaporator connection by the firewall on the passenger side. If that would be the source of your leak, the repair cost should be minimal. You didn't mention if your a/c has been converted to R134 gas or not. That could also affect the cost of the repair although I don't know what a pound of R12 is going for these days but R134 isn't exactly cheap anymore. R134 was very cheap a year ago but not so today. In a way it sounds like you are ready for a new car and if that is the case, let someone else pay for the repair.

[VBdenny]

Yeah, my 90 has the same problem. I am going to try to determine the problem soon. There are several ways to detect a leak such as electronic sniffers, sound detection and good old dye. Either way it is going to cost at a dealer. I may need a new compressor but since the A/C light never flashed and still doesn't I suspect a leak. Luckily I have a 30lb container of R-12 in stock so that isn't an issue.

[RFeldes]

An electronic sniffer is the way to go if you have a mechanic that has one. You could call around. Besides the "O" ring at the fire wall the high pressure hose under the compressor goes out frequently. You would have to put it on a lift to get under there or jack it up. That hose is less than $200. Good Luck.

[akewlguy]

Hello heated LEXUS owner..

First I say you need to get a second opinion. Ask around and find an experienced AC mechanic in the local area. Have them check over the AC unit.

Second get it recharged. If previous owner had system recharged and it worked there is a possibility system is ounce or two short. When system is low over an ounce it shuts down or cycles on and off. So when I recently got my Contour SE recharged it cost $80 bucks..

Now before you get recharge buy the $20 AC kit then hook it up. See if there is pressure then turn on AC. See if system cycles because of low pressure. Try to charge on the low side an ounce or two.. If this works you may have a small leak that requires you to charge yearly.

If system has pressure and the compressor does not start there may be a relay or minor electrical problem. One could take out a blue print and check the wiring or get a professional to inspect.

Now if you go to shop and state what you found you might get a discount. The guy will know that you have a clue, most people dont.

Good luck and check this out since a $200 dollar repair is much nicer then a new $40,000 purchase.

[akewlguy]

Ohh yeah one more thing.

I suspect you tried the recharge already. Sometimes if the system tries to run without oil and freon compressor locks up.. The system typically has a sensor of some sort to prevent operation if low on freon.

Maintenance on any system by a competent technician should be done with solid troubleshooting. Start with the cheepest potential solution and go from there.

Now if one were to put freon into system and monitor pressure they would know quickly if system had a charge. If one were to inspect electrical components and wiring with a volt meter and blue prints they could potentially determine problem or problems.

Reguardless try to find an experienced AC mechanic and make it like you have a clue.. System has pressure... System cycles on and off..

I have heard that replacing the AC compressor has worked for others.

[akewlguy]

Just talked to an expert..

He stated to check out fuses.

Also the clutch coil often goes bad. This engages the AC unit.

Often the compressor is not the issue.. If it does not start there are so many components that support the compressor.

[VBdenny]

Hey cool dude, You brought up a couple of things I haven't thought of. My wife was driving the car when the ac went out and said ir made noise but I never heard it. Perhaps the clutch went bad. No codes, no flashing ac light still. Just no cool air and the compressor doesn't engage.

[jadecuir]

See "AC compressor replace" thread today:I had the same problem, sort of, with my '90 LS. The system stopped working, and I took it to a local AC shop. Diagnosis: bad compressor. I put off repairs for almost 2 years. Then, a friend with AC knowledge and equipment helped me check it out. After recharge and oiling of the system, I've had no problems for 3 months now. The only thing we can figure happened is a leak at one of the valves; there were no caps on any of the three valves! There are now.