Jetdriver69

My 82 had developed a small refrigerant leak. I had to recharge about every 6 months.

One supposed AC "expert" told me after just using a sniffer that my evaporator was leaking and needed replaced. $2500 total cost, yeah right!

I took the car to a local guy who owns his own shop. He charged the system with a UV dye and it turns out the expansion valve has a leak in the front cap. The valve is less than 2 years old, but what can you do?

Ordered a new one from Roger and the estimated labor is a whopping $90 with an evacuation and recharge included.

Just wonder how many people the other AC guy has screwed over the years?

Ducman82

i had the same deal in dayton.... now i am lucky enough i can take it to Greg to get charged.....

Don Carter

I started a thread about expansion valves failing a while back since it just seems like they fail too often and too soon. Now that R12 is $25-35 / can it really sucks when they fail.

I've got a sniffer, gauges, nitrogen, and vacuum pump if you need any help with it, but sounds like you have it covered at a reasonable price.

One think to look out for, may sure they know the low pressure valve is not where it is on most cars. I had one mechanic years ago connect a can of R12 to the high side and he could figure out why it wouldn't take freon.

Jetdriver69

Thanks for the offer, but I'm pretty sure the expansion valve is the only leak.

No dye in the drain tube, in the vents, on the bottom of the car or in the interior foot wells/carpet.

Funny how mine leaked after less than 2 years.

AirtekHVAC

Damn AC guys.....can't trust em....

Kevin in Atlanta

Here's the thing - when they see dye coming out the firewall trap on the PS side they automatically say evaporator. I had the same thing happen to me. But, I researched it and a leak light that would show up in the cabin.

AC guys do not speak 928. The worst outcome would have been ponying up the $2500 and he replaces the expansion valve at the same time - and you might never have known.

j.kenzie@sbcglobal.net

I once bought a cheap Chinese refrigerant sniffer. It not only detected CFC's but it detected water vapor (Not very helpful). Well an evaporator has lots of condensed water on it, so my cheap sniffer was telling me I had an evaporator leak. I accidentally discovered its talent for finding water vapor, by it picking up sweat on my hands. Then I put a wet towel in front of a fan, and it went crazy.
It's in the garbage, and if I ever need to, I will buy a good sniffer.
Good luck,
Dave

bogdann

Had an expert tell me I had a leak from the compressor and quoted me $1800 for part alone. Bought one from Roger and years later it is still in the box as the ac is running fine. Will be getting a new parallel condenser and renewing the whole ac system when my new radiator arrives.

Trust seems to be an issue worldwide.

AirtekHVAC

Say what? I think you are stereotyping my friend!

dr bob

Like any other repair place, they see 'Porsche' and also might know their reputation for problems. Many will quote a price so high that they won't suffer any pain even if lots of other stuff goes wrong. Meanwhile, the systems in the 928 aren't anything special, except there are lots of things to leak especially on rear-air cars.

Sniffing the vents seems to find expansion valve leaks too easily, but it happens. A tech with a sniffer CYA's the job by saying evaporator is leaking, because he can't really tell without digging into the car some. A good sniffer can detect grams-per-year leaks, so there's some technique involved in actually localizing a leak that's bigger.

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My car leaked from new. Lots of dealer receipts for "check for leaks. None found. Evacuate and recharge." I spend a day replacing o-rings, rebuilding hoses, new drier and expansion valves. Flushed the system first. Then evacuate overnight and recharge with R-134a. Then found the o-rings leaking at the compressor manifold. New ones went in, then repeat the evacuate and recharge. I have no reason to believe that the very good local AC shop would do it in much less time. Ten hours at their normal $150/hr, plus parts of course. Worth it to have great really cold AC? On a 100 degree Los Angeles day stuck in traffic? Yep.

sstrickstein

2 years ago I rebuilt my entire system. Every o ring was replaced. The soft rubber High side hose behind the ignition computer was rebuilt as well. I recharged the system at 80% of the r12 factory rating with R134. My system is cold and has not had a problem. Trick here is to start from scratch clean everything with AC system flush completely and recharge. Make sure to use the flush in the compressor as well. And don't forget to flush the evaporator and condenser. If you do this and replace the expansion valve you will have a cold system for years to come.

The Forgotten On

I rebuilt mine almost 2 years ago. Used a griffith's kit from 928 specialists and have never looked back. I replaced everything including the compressor, all 3 soft lines, the o rings, and the expansion valve. I run r134 and the air can get so cold it hurts.

I can literally ask anywhere in my area and they will not work on the 928 specifically.

Most shops hate 928's with a passion when they work on them because most of the time they don't actually read the shop manuals on how to fix them and get them selves in deep sh*t really quick.

But I got lucky and found a retired 928 factory mechanic (one of the first in the country) 15 miles from me. Even he doesn't like working on the ac considering how fiddly and time consuming it can be, he'd rather use the windows and live with it like many here have.

FredR

My recommendation to anyone who has a/c issues [and that probably implies all 928 owners sooner if not later] is to use the dye and UV inspection light method to chase leaks. You have to go through the entire system carefully but it is not that difficult. If you find the source of the leak[s] you deal with them, if you do not then the chances are that the evaporator has gone. To be fair to the 928 I have not seen a single evaporator fail over here in 16 years of 928 ownership [but doubtless some do].

I was chasing a slow leak a couple of years ago that was leaking at a rate that was annoying. The dye test confirmed it was the body seals of the compressor. Given the heat over here, one of the things we do have good capability with is cheap a/c shops manned by chaps who can be very good at what they do. I had the compressor removed by the local agents together with the hoses. A local shop rebuilt/sealed the compressor for me, I had the hoses rebuilt and for the first time on a 928 I seem to have sealed the system [touch wood]. Still have an issue with the control relay that occasionally fails to engage but switching it on and off seems to help matters- doubtless it will fail completely sooner or later.

It is not a particularly difficult system to work on outboard of the evaporator and the thing I fear are those allan bolts on the expansion valves stripping.

Regards

Fred

Schocki

I have seen so many 928s in Germany or Spain now too with not working AC, it is not funny anymore. Many "experts" have no idea what they are doing. As long as they can hook up their fully automated machines to the system, they are happy. Let the machine do everything and do something else meanwhile. They want your money and that you leave their shop ASAP.

Drove my R134a converted 92 GTS in Texas three years and the AC blows very cold air. Same here in Spain in the Summer.