[mcgowaw]

just paid $214 to a yelp recommended ase certified a/c specialist to tell me my a/c system is broke and needs to have everything replaced at a cost of $1600 total, including the 214 i already paid for the discharge/recharge and diagnosis.
needless to say, i got the car back quick.
here's the symptoms, maybe someone can help me figure out what to do next.
first few minutes, a/c works fine (as i'd previously posted but can't find that post now).
then, slowly it starts acting like i turned off the compressor manually. the air goes from 38 degrees to 80 within a span of 10 minutes, after working fine for 20 minutes or so first thing in the morning.
when it stops working, both lines are the same temp.
the vent air stays the same. the compressor still pumps fluid as i can see small amounts of movement in the sight glass. the compressor clutch engages as it always has.
per the tech, after 30 mins, the pressures went from 35-0 low side and 220-190 high side.
he said that represented a blockage, which he said mean the compressor had let go and was circulating stuff in the system stopping it up somewhere.
1. can a bad a/c compressor work fine for 20 mins every morning and then quit working?
2. why would you still have 190lbs on the high side if the compressor isn't compressing?
3. why are both lines the same temp instead of cold and hot like they are when the system is working fine?
i'm looking hard at the txv but he said he'd have to replace the compressor/txv/drier and flushing the lines and recharging.
does that sound correct to anyone?
tony

 

[Mergatroyd]

SoCal prices and rural NC prices at independent shops surrounded by crop fields may be very different. Those prices sound like gouging.

 

[speedy25]

He is right about the problem but the fix may not be the way he sees it.

Yes the compressor still works. But there is a restrictor usually in the evaporator that is partially clogged on your car. It could be debris or it could be water, (?) so the cooling cycles weird. You might be able to make it work with a cleaning and recharge, but if its debris than his diagnosis of a failing compressor is probably spot on.

-SP

 

[O_loung1]

in, for real answers in this thread that i can't provide.

can you give us insight on how the yelp transaction worked? at least with yelp, you can leave some relevant info for other local consumers on this a/c vendor.

a) was the $214 diag fee originally agreed upon? or a surprise?
b) Mergatroyd has a point, each location may have different rates but at $214, that's is more than twice im comfortable paying but i have not shopped for ase a/c tech diag locally here. im just surprised he didn't include the diagnosis fee into the repairs, like a dealership would. almost defeats the purpose of using their service via yelp..

im asking these questions because i can see myself going down the same route in the future. but with my recent tie end rod replacements, when i used yelp for certified mechanics, they cost more than it would if i went into a local service shop. so i went with the service shop instead.

 

[tedmich]

new compressor (Denso 471-1312) is $197 on Amazon...
https://www.amazon.com/Denso-471-1312-New-Compressor-Clutch/dp/B001UCEMVA

drier is $22

DIY if you're CHEAP >

truthfully I lucked out that my 93 worked great when I swapped out the R12, but no one was going to do it for me; R134 is easy!

 

[JohnGD]

If you have vacuum in the system when it's running, then you know there is some restriction. It could be debris, moisture or faulty expansion valve. I'm guessing most likely is moisture, but you already had a vacuum and recharge? Weird.

Everytime the system is vacuumed (for example, routine service after several years, usually around $120), I'd recommend putting on a new receiver/dryer. Cheap enough. Just tell the shop when you're haggling.

If the compressor is bad, then he has to replace all those parts because that's how you won't lose warranty on the compressor. If it'll work for 20 minutes each morning, I kinda doubt the compressor is bad. I'd agree with blockage but be inclined to think it's moisture in the system. What I can't explain is you just had it vacuumed and recharged, so you're not supposed to have moisture in the system unless it wasn't done right.And if the vacuum was done right, then I'd look at the expansion valve next.

 

[phillip123hastings]

Well, at least now you know not to make a mistake like that again, so at least one thing is positive! ( 1600$ seriously? You can buy a new car with that much money )

 

[Mergatroyd]

My understanding could be wrong-- but the vacuum does not draw the water out directly as in drinking with a straw. The vacuum causes the water to vaporize faster and at lower temperature than if it was at atmospheric pressure. Vacuum should be held for at least one hour-- with the pump running. Most shops do not vacuum for that long and they depend on the receiver/dryer to capture the residual moisture, if any.
My knowledge is not sufficient to diagnose the problems you describe.

 

[White95Cam]

Tony, Did the a/c shop change your receiver/drier when they recharged your system. If not, that was money thrown out the window since the R/D captures moisture and crud circulating in the system.
As I posted earlier the rings do wear out in compressors and the reed valves can become damage resulting in low pressure in the system. If the compressor "lets go" it will lock up.
A monumental estimate like you received, same as I did for my Suzuki, is why I did the DIY myself and saved $1100.00. Am I correct that you have a FSM for your car? If so it lists oil replacement amounts, refrigerant amounts and component replacements.
W95c

 

[White95Cam]

My understanding could be wrong-- but the vacuum does not draw the water out directly as in drinking with a straw. The vacuum causes the water to vaporize faster and at lower temperature than if it was at atmospheric pressure. Vacuum should be held for at least one hour-- with the pump running. Most shops do not vacuum for that long and they depend on the receiver/dryer to capture the residual moisture, if any.
My knowledge is not sufficient to diagnose the problems you describe.

Mergatroyd You are correct, vacuum should be pulled for an hour and the system should set for 30 minutes with the yellow valve shut to check for leaks.
W95c
BTW QUOTE FUNCTION IS NOT WORKING!!!!

 

[Stillrunning]

Quote: "he said that represented a blockage, which he said mean the compressor had let go and was circulating stuff in the system stopping it up somewhere."

What does he mean "let go"? If if exploded internally you'd not get any cold air even first 20 minutes, and it would rattle pretty bad. His "repair" replaces just about everything, so he's covered for a wrong diagnosis. I'm not sure I'd condemn the compressor yet. It is after all getting you to 190 when no cold air.

Does the compressor keep turning when you get to "0" on low side? Does sound like restriction on low side though. If the system was never opened to atmosphere then I doubt water.

I think I'd do the TX valve first. It has a temp sensor bulb that may have come loose, so check that. Once you open the TXV lines you can see if any debris.

 

[White95Cam]

The evaporator must be removed to replace the expansion valve. This is the hardest part of servicing the system, so if mcgowaw can do this then the rest of the R/R is very easy.
W95c

 

[CamryFL]

Tony, was this the vehicle you added refrigerant / oil from a can (A/C Pro) recharge in the other thread ?

If all parts on the vehicle's A/C system are original, I can understand the tech's conclusion.

Without knowing if it's water vapor or debris, replacing the receiver/dryer, any o-rings suspect in the system, and valve stems, discharging, pulling vacuum for a period of time (hours), and recharging w/ a correct gauge set would eliminate the possibility of water, but would be lost $$$ if debris..

* IOW, +1 w/ Speedy25's reply here & tedmich's (post #10) reply in the other thread.

FWIW, the diagnosis $$$ isn't out-of-line with what is being charged in this area, complete system replacements run $1,200 - $1,800 depending on type of vehicle / amount of shop labor needed ..

A suggestion, if you decide to DIY, would be to contact a local Auto Recycling yard & ask them to keep a lookout on new incoming stock that they *(you) can confirm has a good system / parts as a donor vehicle, and go that route if needed..

A decent set of gauges ( Pittsburgh brand ) and an air-compressor powered vacuum pump from Harbor Freight ran me about $100 w/ shipping a few years ago, but I would check w/ Advance Auto, AutoZone, etc. locally to see if they 'rent', if this will be a one-time event ..

 

[mcgowaw]

thanks all. i wish i'd spent the 200 bucks at h/f and bought a gauge set and vacuum pump. at least i'd be farther along in the process. i did learn the system has no leaks, so i guess that's something. dunno how long he vacuumed it out but i'm sure he didn't replace anything at all, including the dryer. i was so mad i wanted to spit bullets but i learned something else - yelp reviews are pretty worthless. if you're nice and can convince people they need service when they don't and you do it and it works, then they're happy and glad to give you positive reviews cause they don't know any better. gotta find a better source of reliability on shops for the next time i need one.
tony

 

[heartdisease]

I'm glad you at least have a course of action figured out. I just had my compressor replaced on my pickup. I had the shop do it as I didn't have the vacuum pump or time and I trust my mechanics. 30+ years of experience and honesty. They have never done me wrong. The bad thing is they are about to retire. It will be a pain to have to find another I trust.

 

[White95Cam]

Gauge and pump are in the loan a tool program @AZ. I didn't think a purchase of these was worth the return because of the limited use.
W95c

 

[bwechols]

Wow, that seems extraordinarily expensive. Just out of curiosity, what is the going rate for labor in your area? Around here, labor should be no more than $100/hr. $1600 minus the $214 for diagnosis minus $500 for parts (just a ballpark estimate that should be way too high) means over 8 hours of labor at $100/hr. That's completely outrageous. Not to mention $214 just for a diagnosis is outlandish.

Anyway, rant aside.... the most expensive kit for a 94 6-cylinder on rockauto is ~$250 for a compressor, dryer, and expansion valve. Why not replace the parts yourself (flush system before re-assembly) and just find a decent shop to vacuum and recharge for you? Don't forget o-rings... they're special green ones for a/c systems. Or, even if you buy a vacuum pump, you'll still come out way ahead of the game.

 

[slavie]

Hey, why not take the information straight from the horse's mouth: the
EDIT: little birdie told me:

Condition
Periodically cools and then fails to cool

Symptom seen in refrigeration system
During operation, pressure on low pressure side sometimes become a vacuum and sometime normal

Probable cause
Moisture entered in refrigeration system freezes at expansion valve orifice and temporarily stops cycle, but normal state is restored after a time when the ice melts

Diagnosis

Drier oversaturated state

Moisture in refrigeration system freezes at expansion valve orifice and blocks circulation of refrigerant

Remedy
(1) Replace receiver
(2) Remove moisture in cycle through repeatedly evacuating air
(3) Charge proper amount of new refrigerant


This is just one of the symptoms-cause examples in the FSM - this one seems to fit what you're describing. There is a procedure to test each component of the system, and a plethora of examples.

Or, you could just throw money at the problem... Techs LOVE LOVE LOVE this one. I always wondered why, and just can't figure it out??? They couldn't be doing it for the money, cause, you know, the customer must ALWAYS come first.

 

[CamryFL]

At least in this area Slavie, A/C system work commands a premium, barring the standard 150% markup over retail cost of parts many shops build in..

EPA & Tech certs, evac equipment costs, etc. are all bundled into the cost of repair here, on top of hourly shop rate.

With the '00 Camry pushing 240,000 miles here, if the expansion valve appeared good / no metal found, I would be suspecting the Condenser assembly, Compressor, and Receiver/Dryer, and all o-rings involved (under hood items) as candidates for replacement due to age / condition.

Tony, if you strike out on tool loan in your area, have access to an air compressor, and are interested, PM me: I'd be willing to send out the manifold gauge set & vacuum pump sitting here for you to use for the duration of the repair.

 

[White95Cam]

Remedy
(1) Replace receiver
(2) Remove moisture in cycle through repeatedly evacuating air
(3) Charge proper amount of new refrigerant

(4)Add 10cc of oil to suction side of the compressor.
You only need to vacuum the system once for 1 hour, otherwise if you reopen it to air you will need to replace the r/d again.
W95c