Out of options for cold AC -- I'm spent.

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The expansion valve removal is quite easy IMHO.
 
Guys, measured the low/high and even went to earlier shop to double-check. Recharged 4oz.

LOW SIDE = 20psi
HIGH SIDE = 250psi

Seems a little out of range, what would this indicate? Pretty humid here today, ambient temp ~98-99F.

Start the truck, set to 1500rpm with windows down, recirc + high + AC and I get vent temps of 70F. Much better actually than the 78+ I was getting earlier.

Also noted that setting the fan on HIGH produced about 7F higher vent temps than the 3rd (just below high) fan setting. Is this expected???
 
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Allright guys lets get to the bottom of this a/c issue, after reading all post i still haven't seen any a/c high / low pressures listed. These will be key in diagnosing this issue. I have had 5 80's and still have 2 of them and the 2 i have now have had the exact same issues and it's been the expansion valve on both vehicles times. Just repaired one of them today. When an expansion valve sticks the low pressure will typically go to 10psi or lower, (restriction) the high side pressure can vary but will typically climb to above 250 and up. A properly charged and operating system should show low pressure of 28 to 30psi, the high side depending on ambient temp 170 to 225psi. plus or minus a few pounds is ok for our older vehicles as the compressors wear with age.

Post the a/c pressures and we'll get you there.
Charleston Toyota Lexus Mechanic Lex-Tech James Island West Ashley Folly Beach

Guys, measured the low/high and even went to earlier shop to double-check. Recharged 4oz.

LOW SIDE = 20psi
HIGH SIDE = 250psi

Seems a little out of range, what would this indicate? Pretty humid here today, ambient temp ~98-99F.

Start the truck, set to 1500rpm with windows down, recirc + high + AC and I get vent temps of 70F. Much better actually than the 78+ I was getting earlier.

Also noted that setting the fan on HIGH produced about 7F higher vent temps than the 3rd (just below high) fan setting. Is this expected???

Did you read the above post? I don't know squat about A/C systems but I would start here if it were mine.
 
Are you talking about the expansion valve?

Yes. He said that when the valve sticks the low pressure will be lower than the normal 28-30 psi range and the high pressure will be 250 psi and up. That fits your description.
 
Yes. He said that when the valve sticks the low pressure will be lower than the normal 28-30 psi range and the high pressure will be 250 psi and up. That fits your description.

These are the numbers I'm experiencing, no matter how much r134a went in and I evac and recharged twice. I was at 20/250 as well and just couldn't get the low side to go past 20 psi :mad:

I ordered an expansion valve and a dryer from the outfit that was mentioned (in my thread) by ToolRUs out of AZ. Hopefully in the next couple of days, I'll install the parts and recharge and see what happens.
 
I'll be eagerly and anxiously watching your thread! I'll go read said thread now for clarification, but was OEM too pricey vs. getting parts from the other shop?

Yeah, you could say that! I bought three items for the cost of one oem expansion valve.
 
I think it was somewhere north of $30 or $40. The one I bought cost $11.
 
I'd stay away from Denso parts. They've fallen off quite a bit. Somewhere around 2001 they began manufacturing crap.
 
I'd stay away from Denso parts. They've fallen off quite a bit. Somewhere around 2001 they began manufacturing crap.

I'm thinking he means the quality "has fallen off quite a bit".

If not Denso, then who ?
 
Yep, the quality is horrible now. Go with after market parts, as aforementioned. You could buy from me for example. I could sell you a Denso compressor, expansion valve, yada yada, but I'm not going to put you or myself in that position.
 
I'd stay away from Denso parts. They've fallen off quite a bit. Somewhere around 2001 they began manufacturing crap.

My experience with Denso is quite different. We sell about 100 Denso compressors a year, for everything from Acura to Toyota. I've seen maybe 5 true defective units in the past 8 years. Yes, the 10S20 series are problematic (they're used on Suburbans/Tahoes, etc) but much of that is due to the poor design of the system (GM has admitted as much). I don't see problems with Honda's using 10S20's. I wouldn't hesitate to use Denso products on my own vehicles-and I have. Much of the compressor line used to be remanufactured, which Denso did better than anybody, but in the past year, they have gone to new product, and as a bonus, lowered the price. The driers and expansion valves are more expensive than the offshore products, but my opinion is they're worth the few extra dollars. No, I'm not on Denso's payroll-but I do like selling their product-it fits, works like it's supposed to and lasts.
 
I read this whole thread last night. I have a black LX and can relate. You will find the problem. In my case the steelership had put 18% too much oil in the system. I found this by finely taking the truck to a well recommended shop. Like you I had been diving myself crazy replacing part after part. One thing I did along with the blue clutch mod was adjust the valve. That alone made a big difference on how the truck cooled even before the pusher fan. Now my center vent temps stay in the forty's even on the trail in the desert. Don't lose heart you will get it working right!!
 
i'm no a/c man by any stretch of the imagination, but a buddy of mine has and lx which had an actuator go out for the recirculate air vent (not sure of official name). It' hard to cool 100 degree outside air in this texas heat. we closed the vent permanently and he finally got the temps he was after. the vent can be found above your blower behind the glove box. good luck
 
i'm no a/c man by any stretch of the imagination, but a buddy of mine has and lx which had an actuator go out for the recirculate air vent (not sure of official name). It' hard to cool 100 degree outside air in this texas heat. we closed the vent permanently and he finally got the temps he was after. the vent can be found above your blower behind the glove box. good luck

This is yet another reason I love my 3FE. Mechanical hvac switches! Slide lever and IT moves cable to control the door. Brilliant.
 
Time to have this thread resurface as hot is here again. I have a new expansion valve. I thought I had some links on how to replace this from this site, but can't seem to find it now. Anyone have any description + pictures?

Thanks,
 

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