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Ac issue

Ryan Duke
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Ryan Duke New Member

Ryan Duke

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I have a 2001 silverado and the ac blows cool are when the ac is on and intermittently blows cool to hot when driving.  No lines are leaking and pressures are perfect.  I've looked at everything and can't find a issue with anything. Any help or advice would be greatly appreciated. 

Black02Silverado Senior Enthusiast

Black02Silverado

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Posted

How many miles are on the truck?  Is your fan clutch working well? Have you tried cleaning the front area of the radiator/condenser?

txab Senior Enthusiast

txab

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As noted above.... check evap. for bent fins. Make sure it is free of bugs, etc.... Make sure fan clutch is working properly. Just because your radiator doesn't overheat, doesn't mean your fan clutch is working  top efficency.

 

You could have a weak compressor. A slipping clutch. You say your pressure is fine... are you  using AC gauges or simply the gauge on a can?

Brian715 Enthusiast

Brian715

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Posted

I had an 04 work truck that the blend doors were haywire and it would all of the sudden switch to hot while driving down the road. If you stopped and shut it off it would go back to cold. Easy fix but the truck had over 250,000 on so the boss sold it before we fixed it. Easy way to check that is you can unplug the blend door actuator when it's on cold and see if it stays cold. 

Sharpz Enthusiast

Sharpz

Posted
Posted

As Brian said, check your blend door actuator.  On my 99 new style it did that exact thing. I had to have the passenger side of the temp setting all the way down on cool, and the drivers side up 1/4 inch from that for it to blow cold on my side. If I didnt have it that way, a fair amount of times I would have to shut the truck off and hope it worked, that is till I discovered the 1/4 inch trick.

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