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Discussion Starter · #1 ·
There's something up with my A/C. When sitting at idle, it works fine, but when I get moving down the road, it is worthless. It had enough freon, but was on the low end of good, so I recharged it with an auto store can this weekend, but that didn't help. Is there some kind of sensor or safety switch that could be killing it when I am driving?
 

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hydraulic lifter crew
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i had the issue of cold on drivers side and warm on passenger.
i recharged with two cans freon and it seemed to help out.
air is running right at 59 degrees so far. its supposed to be 100 degrees
today, so we'll see how it REALLY works.

compressor could be going the way of the dodo if it doesnt cool after you recharged it.
 

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you could check you low pressure switch on the dryer. you could plug a jumper wire in the harness after disconnecting it and see if it cycles at high idle.
 

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Same issue with mine,,, Look under the hood, where the water drains, make sure you have a L-Shaped drain hose pointed towards the ground.. I first noticed mine when there was little air coming out the vents and the fan sounded really loud, I turned off the A/C and noticed that the air started coming out faster...I assumed that the coils were frozen, what was happening was the water was being forced back up into the drain and freezing because there was no hose at all, well its works much better with the hose installed and also running the air off and on from the outside source to help melt any drain water on the A/C coils...
 

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Discussion Starter · #5 ·
Well, after testing a few different scenarios, here's what I have...

1) When I first start the truck and take off, I get cold A/C for about 5 minutes, then it is as if I shut the A/C off and am running just vent
2) When it is working, it works in both fresh-air and recirc mode.
3) When it is cold, it is cold on both L and R sides, so that doesn't seem to be the problem.
4) After the A/C dies, if I shut it (air) off for 5-10 minutes while going down the road, then turn it back on, it will work for a few minutes, then stop.

The A/C works, but something is causing it to shut itself off. I don't know if it is a sensor, preasure, freezing, or anything else. I ran a parts store recharge can with a guage. It was a little low, but not enough to make a difference so freon shouldn't be an issue.
 

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Discussion Starter · #7 ·
Airflow does not decrease, at least not by much. Last night I left it off until I was two blocks from home and when I got there, there were a few drops of condensation under the A/C.
 

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well I thought it might have been the coils freezing up, but you would have decreased airflow with that..And the fan noise would have increased on the Passenger side a lot..If you only had a few drops, your humidity level was either low or there just wasnt any exchange of heat going on or freon gas moving through the coils. but Im still wondering about your statment that it worked while not moving...I think I would still check the drain and install the L-shaped hose if not there. other then that, you need a good AC guy to take a look.. I know these 03's and 04's really had some crappy AC/s.
 

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Discussion Starter · #9 ·
A little update, I checked the codes tonight and saw a "P0647 A/C Clutch Relay Ctrl Circ Hi"

Could it be that at the higher rpm's the A/C clutch is still grabbing hard and turning too fast?
 
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