motolex722

iTrader: (4)

So i've been having a lot! of a/c problems the past 6 months. My compressor first went bad last fall but decided to not replace it till the spring. I had my first compressor replaced in march, and immediately it didnt work so my dad, a toyota master tech for 12 yrs now, got it exchanged. The 2nd one worked for 2 months with MINIMAL use until the clutched burnt up. Now on to my last compressor. Not even 2 weeks & VERY minimal use later, the clutch is burnt up again! and now this time, my a/c unit inside the car is constantly switching from fresh air to recirculate no matter if you set it to one or the other or set it to auto. Also its not reading the outside temperature correctly. it's saying that it was 60deg yesterday when it was clearly pushing close to 90deg. If anyone has any ideas on what the problem(s) could be, please post a reply. I'm in my 3rd year of college and cannot afford to keep dumping $400 compressors in this car on a monthly basis.

Mr Jokster

iTrader: (8)

why isnt warranty not covering the compressor? It does come with some type of warranty right? and if its just the clutch burning up, why you replacing the whole thing? And as pops as a master tech, cant he get you a diagnosis for free?

ac921ol

iTrader: (1)

ambient air temp sensor?? not sure if these cars have one tho. (i know this was going on on my audi, and when the outside temp would read off the chart, it would mess with my AC no matter what setting)

And your dad with all his experience has no idea?? never seen an issue like this?

speedaddic

iTrader: (10)

yes, there is a temp sensor located by the front grille/bumper, but that is only for the outside temp and has nothing to do with the ac staying on fresh air.

motolex722

iTrader: (4)

i posted this w/o my dad getting a chance to fully diagnose the problem again. Hopefully i can get a warranty for this compressor. The last compressor was pulled of a 49K gs at a lexus junkyard the dealer uses so i'm not sure if they offer warranties. My dad will get a quote on a new clutch tomorrow when he returns to work but i just wanted to run the problem through you guys to see if you had any ideas. Mocking my dad's experience isn't necessary, just thought i'd see if any of you guys have run into a similar problem.

werewolf

slow down

if the car is switching from fresh air to recirculate by itself, is it also activating the A/C?
Does it turn the A/C on and off a lot (by itself)?
The clutch could be burning out b/c the AC is turning on and off all the time. I wouldn't buy a compressor until I solve what sounds like an electrical problem 1st.

Are there any fuses involved? Check for the cheap fixes 1st.
How long has the temperature reading been bad? Just now or for all the previous compressors?

del3180

Sorry to hear about your situation
Does your mechanic completely flush out your AC system before installing the new compressor and clutch? When a compressor goes bad, it can also dump garbage down the lines, which would then need to be flushed properly before installing the new unit.

Rich23

iTrader: (3)

^^^^^^ ++++1

pwesseler

This could be part of the problem, I would not use junk yard parts while working on the AC system.

motolex722

iTrader: (4)

No the unit doesn't switch itself on and off by itself. I noticed while i was driving home with the a/c on that it wasn't as cold as it was earlier that day and then i saw the recirculate/free air light going back and forth while the a/c light remained lit. i tried to see if maybe if i put it on auto it would stop. It didn't so i tried then switching it manually to just recirculate, then just fresh air but neither of the 3 scenarios worked. It continued to keep switching by itself so i turned it off altogether to prevent any further damage which the next day happened anyway, the clutch went again.

all the fuses and relay's are fine. my dad did disconnected it then reconnected the outside air temp sensor and now it is reading correctly. i guess it reset itself?

motolex722

iTrader: (4)

yes he does.

motolex722

iTrader: (4)

my dad's diagnosis is that the system is building up too much pressure & not an electrical problem. He does flush the system completely but he'll do it again this time to be positively sure there is not blockages. Also along with our 4th compressor he's going to install a new condenser as well. hopefully this solves our problem. I'll keep you all updated. thanks for bouncing around ideas.

sakataj

iTrader: (182)

i was wondering the same things nathaniel

he isnt mocking his experience but if he's a certified master for toyota and he keeps putting in compressors he should be looking for the other issues....i mean after the 2nd one he wouldnt put in another one if he knew what was good for him without figuring out the rest of the issues.... which would be were/what is causing the restriction that is causing the system to be over pressured

thats true and 99% of people dont flush systems....if u look at every ac post i have commented on, i have always suggested flushing AND replacing the drier/expansion valve.

100% x2, DONT use used parts on a a/c system, its not worth doing stuff like this again yet alone 3-4 times


if your car is over pressurized you have a restriction someplace thats obvious but the first place i would go hunting is to make sure that your dad isnt over pressurizing the system and then i would check (replace) the expansion valve/drier. doubtful the condensor is clogged but it is possible....

dcz

OK First off, everytime you replace a compressor, you need to REPLACE your drier, too. When a compressor fails, it usually shoots metal pieces into the lines and accumulates in parts of the drier or condensor, or other parts.. Its important to change the appropriate parts if youre going to change the compressor. Also ALWAYS flush the lines if youre replacing it. That would explain your compressor screwing up after you changed it the first time... and the second.... Check out a DIY I posted for AC comp/drier/condensor install... It has all the info you need.

As far as your problem now goes with it recirculating etc...

system is overcharged... The reason it switches form outside to recirculate is due to an increase of pressure in the system. When the AC is on recirculate, the AC comp doesnt have to work as hard to maintain the AC cabin temperature because it doesnt have to work as hard to cool it. (this means less pressure in the lines)

When youre taking in outside air (especially in the summer) the AC comp will have to work MUCH harder to cool the outside air to the temperature you have it set on. You can definitely tell if it is overcharged if youre driving down the freeway and you feel your car jolt back and forth with the AC compressor coming on and off.... I would recommend hooking it up to some guages and looking at the high side pressure. Lexus comes with a high pressure shut off switch to disengage the compressor inorder to prevent it from getting destroyed. That would be why your clutch is screwed bc of the constant engange/disengagement.

Thats the down and dirty, but I can explain it in further detail if you need... I would release the pressure and take it to ANOTHER shop to get it recharged.

sakataj

iTrader: (182)

i second the drier replacement....thats why i said it in the post above yours

as far as your DIY, as i said in it, yes its good but this isnt something a average joe schmo should be even attempting. people dont understand that freon CAN/IS a dangerous item to mess with.


and your last one made me laugh because you said to take it to another shop, which i agree with (but for a different reason) but its his DAD doing the work so that doesnt say much about him being "master tech for toyota" and its hard to tell your pops you dont trust his work