a/c warm/cool not cold intermitently?

Joined
Aug 26, 2005
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my a/c twice in the last month was blowing warm to cool air but not the stinging cold that it use to be.
each of these days it was past 80 degrees outside, but when the ambient temp is cool all was fine.
my cruiser isn't overheating-cooling system overhauled after I bought it, with new radiator, thermostat, fixed leaking heater hose at firewall.
so after doing some reading I think I need to look at freon, compressor, fan clutch, a/c cut switch...
anything else to tell the mech-I won't be fixing this myself
headgasket (finger's crossed) is original and via the negative bubble test and no overheating is assumed fine.?
 
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Jan 25, 2007
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my a/c twice in the last month was blowing warm to cool air but not the stinging cold that it use to be.
each of these days it was past 80 degrees outside, but when the ambient temp is cool all was fine.
my cruiser isn't overheating-cooling system overhauled after I bought it, with new radiator, thermostat, fixed leaking heater hose at firewall.
so after doing some reading I think I need to look at freon, compressor, fan clutch, a/c cut switch...
anything else to tell the mech-I won't be fixing this myself
headgasket (finger's crossed) is original and via the negative bubble test and no overheating is assumed fine.?

Just had the same problem. blend door was not closing all the way. Rigged it for now, looks like the servo is not closing it all the way. Hope this helps! Gotta have A/C!:beer:
 
Joined
Aug 26, 2005
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would the blend door account for the difference when it is cold or hot outside?
 
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Nov 27, 2003
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the fan clutch- that's my bet. I called c-dan and got the goods, takes a few min to pop it in. a/c is much colder now and my temps are rock steady. I wish I had done it earlier...
 
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Jan 23, 2007
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Texas, of course.
When it goes over 80 outside and the A/C starts getting warm that means your low on freon. Look for the sight glass on your drier while the A/C is on and see if theres bubbles. If you see them you're low.
 
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ok, my service guy said I was 1lb low on freon and more was added. they said they did a "performance check" on the a/c system and that was the only thing found. so it has been 4 days all is well, but today it was a cool 60 degrees and after a car wash (if that has anything to do with it) again it is blowing warm.

how do I check if the blend door is working? I can check the fan clutch by rotating the fan-with the engine off-correct?
I have brought it to two local service guys, one is a toyota specialist-dreading having to take it to the stealership.
 
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Texas, of course.
You might want to see if the clutch is engaged on the compressor when it blows warm. Had a Ford terrorize me w/ intermittent cooling problems and it turned out that under certain temps the clutch wouldn't engage on the compressor due to the air gap on the clutch hub. Took the clutch apart,subtracted a few shims, put it together and it worked perfect. Not saying this applies to yours but start w/ the basics.
 
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This sounds a bit like an expansion valve icing problem, As the AC works harder, the difference in temp between outside the lines and inside gets greater, and the moisture in your system makes ice which blocks off your expansion valve. I had a similar problem that when it was hot out, it would blow cold for about ten minutes and then go warm. The bad news is that you have to open up your system to replace it.

Edit: ensure the check the sight glass and confirm compressor and fan operation as stated above before you go tearing into stuff.
 
Joined
Aug 26, 2005
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so annoying-with closer observation this is what I noticed:
with the a/c compressor switched on, the air is warm (as if the heater was on low) whether fan blowing high or low
when I turn off recirculate and outside air is mixed, the air is cooler b/c it is cooler outside
if I turn off a/c switch and allow outside air with the fan this evening, the air was even cooler than the above two senarios

this all restarted just driving home-the car had been sitting from 8am-530pm in the parking lot-a/c turned on, nothing but warm

now coming home from the in-laws about 4hrs later everything seems to work0a/c is cold
arrrggg
thanks for letting me vent
anymore suggestions would be appreciated?

can an a/c compressor work intermittently?
don't think fan clutch is the issue b/c of the intermittent part.
I will make sure there isn't any freon leaks the shop put some dye in the system
 
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Mar 28, 2003
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Somewhere in NJ
ok, my service guy said I was 1lb low on freon and more was added. they said they did a "performance check" on the a/c system and that was the only thing found. so it has been 4 days all is well, but today it was a cool 60 degrees and after a car wash (if that has anything to do with it) again it is blowing warm.

how do I check if the blend door is working? I can check the fan clutch by rotating the fan-with the engine off-correct?
I have brought it to two local service guys, one is a toyota specialist-dreading having to take it to the stealership.
I don't think it's your blend door. You already have observed a leak in the system resulting in low refrigerant. The AC shop did nothing but put more refrigerant in which temporarily made the AC work again...so I'd bet it's just leaked out again. You need to find the leak and fix it.
 
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This sounds a bit like an expansion valve icing problem, As the AC works harder, the difference in temp between outside the lines and inside gets greater, and the moisture in your system makes ice which blocks off your expansion valve. I had a similar problem that when it was hot out, it would blow cold for about ten minutes and then go warm. The bad news is that you have to open up your system to replace it.

Edit: ensure the check the sight glass and confirm compressor and fan operation as stated above before you go tearing into stuff.

Don't know about the icing but on my truck replacing the valve & cleaning 14 years worth of gunk from the heater core/recharging/changing the receiver/dryer etc took care of it (300some odd bucks @PepBoys last November.
 

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