GMC/Chevrolet Truck/SUV When starting new posts, please specify YEAR, MAKE, MODEL, ENGINE type, and whatever modifications you have made.

99 Sierra AC Issue: It's getting hot down here...

Old 04-12-2012, 08:30 AM
  #1  
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
tulse's Avatar
 
Join Date: Apr 2012
Posts: 10
Likes: 0
Received 0 Likes on 0 Posts
tulse is on a distinguished road
Default 99 Sierra AC Issue: It'* getting hot down here...

AC works fine. It'* cold and it blows, but after ~10 minutes it just stops being cold (but still blows).

I checked the refrigerant with manifold gauges. It'* good.

I'm stumped. Where do I check from here?

Thanks all.
Old 04-12-2012, 08:42 AM
  #2  
Senior Member
True Car Nut
 
jwfirebird's Avatar
 
Join Date: Dec 2009
Location: western,ny state
Posts: 9,616
Received 579 Likes on 497 Posts
jwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond repute
Default

theres a actuator in the duct under there that controls the temp, see if thats moving right
Old 04-12-2012, 08:53 AM
  #3  
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
tulse's Avatar
 
Join Date: Apr 2012
Posts: 10
Likes: 0
Received 0 Likes on 0 Posts
tulse is on a distinguished road
Default

Originally Posted by jwfirebird
theres a actuator in the duct under there that controls the temp, see if thats moving right

Thank You, JW. Can you tell me where that actuator is. I'll go look now.

There are two actuators, driver and passenger side. Is that right?

Thanks again.
Old 04-12-2012, 09:00 AM
  #4  
Senior Member
True Car Nut
 
jwfirebird's Avatar
 
Join Date: Dec 2009
Location: western,ny state
Posts: 9,616
Received 579 Likes on 497 Posts
jwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond repute
Default

should be 3 probably ive never had to replace one myself. one for each side and one to switch between vent floor and front. should look like this and the shaft should move visibly

Amazon Amazon
Old 04-12-2012, 09:28 AM
  #5  
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
tulse's Avatar
 
Join Date: Apr 2012
Posts: 10
Likes: 0
Received 0 Likes on 0 Posts
tulse is on a distinguished road
Default

Found one on the passenger side. I found the actuator that controls Floor/Defrost/Vent etc. That one is moving and working fine. Of course, that'* not what I need. It looks identical to the one you posted from Amazon.

I'll keep looking. The dash is off the truck, so hopefully this will be easier.

Just to be clear, the other two should look or function about the same way and control "barn doors".

The AC doesn't start blowing hot. I just loses its cold.
Old 04-12-2012, 09:34 AM
  #6  
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
tulse's Avatar
 
Join Date: Apr 2012
Posts: 10
Likes: 0
Received 0 Likes on 0 Posts
tulse is on a distinguished road
Default

I think the second is under the glove box. I am going to pull that off now. I'll report back.

Thanks for you help, JW.
Old 04-12-2012, 10:33 AM
  #7  
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
tulse's Avatar
 
Join Date: Apr 2012
Posts: 10
Likes: 0
Received 0 Likes on 0 Posts
tulse is on a distinguished road
Default

I found the second temperature control. It'* fine. Working normal.

I'm think compressor clutch now?
Old 04-12-2012, 12:11 PM
  #8  
Senior Member
True Car Nut
 
jwfirebird's Avatar
 
Join Date: Dec 2009
Location: western,ny state
Posts: 9,616
Received 579 Likes on 497 Posts
jwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond repute
Default

well you said you checked it with gauges, was that while it was malfunctioning or working? does it do it just sitting there or does it while your driving?
Old 04-12-2012, 02:05 PM
  #9  
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
tulse's Avatar
 
Join Date: Apr 2012
Posts: 10
Likes: 0
Received 0 Likes on 0 Posts
tulse is on a distinguished road
Default

Originally Posted by jwfirebird
well you said you checked it with gauges, was that while it was malfunctioning or working? does it do it just sitting there or does it while your driving?
Driving and sitting idle. I rented the gauges and put them on after the temperature of the AC went down while idling. A/C was at max. Pressure was fine.

If I turn the truck off for 2 minutes, then turn it back on, I get cold air again.
If I turn the AC off while driving, then turn in on after 2 minutes, I get cold air again.
Old 04-12-2012, 04:13 PM
  #10  
Senior Member
True Car Nut
 
jwfirebird's Avatar
 
Join Date: Dec 2009
Location: western,ny state
Posts: 9,616
Received 579 Likes on 497 Posts
jwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond repute
Default

next i would back probe the plug for the clutch and see if its getting power while it malfunctioning or if something is shutting it down

Thread Tools
Search this Thread
Quick Reply: 99 Sierra AC Issue: It's getting hot down here...



All times are GMT -4. The time now is 11:55 PM.