AC not blowing cold at idle

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TheAutumnWind

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I've read clutch fans aren't that great in the cooling dept if you're sitting still. Electric fans cool great once they kick in while idling.

Clutch fans can potentially move more air than electric. The clutch may be ready to be replaced.

OP can you hear your fan at idle? It should be pulling enough air to for it to be plenty noticeable if its warm enough that you need to run A/c.

Otherwise get some gauges and check the pressure in your system.
 

ks03

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So you had the same mediocre cooling when idling with your clutch fan?

Yep, seemed like by the time I came to a stop at a red light the ac was hardly doing anything. Holding the revs just above idle helped, but a PITA. I didn’t want to travel with dogs in the summer before, leaving the ac on while parked and going inside for 10minutes didn’t seem acceptable, afterwards it can maintain.
The wife even thinks the blackbear tune was a reasonable use of $ ,since it allows the pcm control, couldn’t care less about anything else it did.
 

corvette744

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Yep, seemed like by the time I came to a stop at a red light the ac was hardly doing anything. Holding the revs just above idle helped, but a PITA. I didn’t want to travel with dogs in the summer before, leaving the ac on while parked and going inside for 10minutes didn’t seem acceptable, afterwards it can maintain.
The wife even thinks the blackbear tune was a reasonable use of $ ,since it allows the pcm control, couldn’t care less about anything else it did.
Same problem here i can care less about anyone in the tahoe i care about the dog when i run into store and leave it running.Im going to check that out more this summer its 40 degrees here so dont need it yet.If everything is right with pressures and i have a new clutch fan on it now.I will just install a cheap elevtric fan and turn it on when its running..I have one on my big block street car easy to install.The electric fans seem like a big hassle to install.
 
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BatsTDK

BatsTDK

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OP can you hear your fan at idle? It should be pulling enough air to for it to be plenty noticeable if its warm enough that you need to run A/c.

No it’s pretty quiet at idle. I think maybe temps haven’t warmed up here enough for it to kick in more?
 

TheAutumnWind

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No it’s pretty quiet at idle. I think maybe temps haven’t warmed up here enough for it to kick in more?
if the truck is up to operating temps and you are sitting idling for awhile and its warm enough to run a/c you should hear that thing sucking air imo.

If you think the clutch fan is good then get gauges and tell us the reading. They are like $50. If your pressures are good then aux fan is an easy project
 

ROGELIO A GUZMAN

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I’ve noticed at stop lights and idle that my AC is barely cold. Once I get the engine going, it’s nice and cold.

I’ve read conflicting info that the condenser isn’t getting the airflow it needs so it’s not effective at idle. Or it needs a recharge. Or it’s overcharged.

Anyone else experience this?
Fan clutch time. I had that issue. Replace the fan clutch. I put a severe duty fan clutch. Here in california we have alot of traffic. Helps keep truck cooler. And also a 160 thermostat. I also replaced a china radiator the last owner put in. Replaced with a ac delco and all over heating issues stopped.
 
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Javie

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I've read clutch fans aren't that great in the cooling dept if you're sitting still. Electric fans cool great once they kick in while idling.
Yup i'm willing to bet it has something to do with the clutch belt. Fan spins slower at idle so less cooling.
 

Mooseman93

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I’ve noticed at stop lights and idle that my AC is barely cold. Once I get the engine going, it’s nice and cold.

I’ve read conflicting info that the condenser isn’t getting the airflow it needs so it’s not effective at idle. Or it needs a recharge. Or it’s overcharged.

Anyone else experience this?
Start simple. Check the tensioner on the ac belt. I've had two now that lost tension. There was still enough that it worked decent at highway speeds but at idle it was hot. It's a $30 part and not super difficult, if that's the culprit.
Otherwise, yeah the fan clutch would be my next target.
Also, don't trust the "free" guages that come with the cans of refrigerant. They're ok in a pinch but not really what you need to do the job right. If it's low, a common spot for the leak is the low side schrader valve.
 

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