Just finished a 13,000 mile trip with everything working great on an 03. Next time I start it and turn on the AC, cold is coming out the two driver vents, but warm out the three passenger vents. Any ideas??? I have no clue as to the venting on this truck. My wife will love you forever.

SweatingBob

 

Bob....
I believe that this is a blending door issue.... I was not aware that the 2003's had this issue and yours may not be the norm, but I do know that the late models 2005-2006 are plagued with this. Not to panic, but I understand that the repair requires the removal of the dash to fix. Check with others on this site for their opinion as they may be more familiar with your year.

 

Even the '03's have this issue.
Also could be low on freon so check that first before diving into the ventilation system.

MikeyB

 

You might be right, Mikey - - it was freezing up coming home. Had to keep turning off the compressor every hour or so, let it thaw, then kick it back on. However, I am getting cold air out the driver side, so we are cooling - - just not coming out the vents right. Strange.

 

I'm having the same issue. I put thermometers in the vents today. Driver's side is 15 to 20 degrees colder than passengers side most of the time but after a few minutes the passengers side will close the gap, then warm back up.

 

From my understanding the driver side vents get the first pass from the evaporator, and the passenger side gets the second pass, so the temperature differential.

Fiverbob, getting low on freon will cause the freezing condition.

MikeyB

 

Yep, I was crossing my fingers it held long enough to get us home. Just been too busy to go get some refrigerant and do it. Sure don't want to have to pull that dash apart. I will see what the pressures look like over the weekend and add refrig if it is low. Then, see what the two sides do.

 

Fiverbob,
Go to my gallery to the see the specs for the A/C system.

MikeyB

 

I have a 06 and just had mine in the shop for this same problem. The dealer put in a O ring-tube assy. and it seems to have fixed the problem. Paperwork says suction line leaking at o-rings which also caused low freon. Hope this helps.

 

Just bumping this back to the top to tell the "rest of the story." Took the beast in for testing of the pressures - - definitely running low. Vacuumed the system - - it had about 1 pound in it - - should be something like 1.8. Recharged it. Then the mechanic noted that the little 90 degree hose that it attached to the condensate discharge line coming out the firewall was missing. He commented on GM products that is common and allows air pressure when running on the highway to force the discharge back into the chamber where it freezes. He did drop the fan and found the screen to be quite clean. So, I found a replacement and installed.

Conclusion: the recharge has the AC running like it did when new with both sides cooling - - it has not frozen back up. Thank goodness for a good honest tech with some common sense.

 

Fiverbob,
With these new R134 systems and some R12 systems refridgerant dosen't dissappear without having a leak some where. The old R12 system used compression fittings that would leak over time. The new systems use compression and rubber o-rings to prevent leaks. I hope it dosen't but it may leak down over the next month. Did the tech find the leak? Did the tech pull a vaccum on it and leave the system closed for 30 min to check to see if it had a leak?

 

Fiver Bob.... Spooler is so right, if it was low on refrigerant and there was no repair made, Kind of a waste of time. Had this issue, been there done that and a pain in the butt to make multiple trips.
Good luck

 

Hopefully the tech did the vacuum test. When I do my own system I usually wait for one hour.

MikeyB

 

A vac was pulled and sat for 45 minutes with no change. He added dye and oil before refilling. This has been coming for a while now, so any leak has to be a small one. We will see shortly and put the light on it and look for the glow. It has been my experience (limited on auto air, more on commercial ac) that "looking" for a very slow leak can be a very slow process producing a very high bill. I like the dye and light method. We will see what happens. Thanks for the ideas. Just wanted those interested to know what had happened.
Bob

 

Ok, I Read All The Other Threads On Ac Problems & I Am Confused. The Passenger Side Is Not Only 10 Or More Degrees Hotter, But Also Doesnt Blow As Hard As The Driver Side. Is This The Blend Door? Is The Blend Door The Same As The Recirculating Door? Any Help Would Be Appreciated.