A/C Issues
 

2008 4.8 w/4 way climate control plus ventilated front seats.

I'm having issues with my A/C system. It can produce cold air, but it seems I have a distribution problem.

With 85 deg F outside air, I get nothing but warm air, 90 deg F + out of the vents to the left of the steering wheel. The left center vent produces about 68 deg F air, The right central vent is about 58 deg F, and the far right vents are about 68 deg F. The rear A/C is producing about 64 deg F on both vents. The Seat A/C seems to not work at all.

About a month ago, I had the front blower motor replaced. I don't know if anything I'm experiencing now is related to this job being done, (perhaps improperly?) But all these issues are since that job was done.

If this problem started once that repair was done then they may have screwed something up in the repair. Only other thing I can think of is your refrigerant needs recharged??

With most normal cars, the left most vent is usually the coldest. And I'm getting hot air from there; cold from the middle vents. But this is definitely not a 'normal" system with all sorts of electric controls.

I'd say somoene messed up on the prior work...see what they say.

I don't think you're even getting cold air. A properly working AC gives you ~40-45 deg air.

I've had problems with the air circulation seems to shift directions. It will be blowing really good and all of a sudden I hear a clunk (shift) and the air gets blocked by something. Some times when I take a hard right turn or break pretty hard it will go back to normal. I had the blower motor replaced thinking that was it but no luck.

Can't figure it out. A flap or something. Don't even know where to start looking

Model/model year? Condition of micro filters/pollen filters? How do you have the AUC button set...is the left LED illuminated? If yes, the auto-recirculation is initiated which can open/close the fresh air flaps based on specific criteria.

BTW...only asking because the things asked can't be ascertained from your post. :)

2007 4.8.

I usually have the led button off. Never noticed any difference between having the air circulation on or off.

Definitely I'm getting cold air. It WILL cool the car in 85 deg weather. I was a bit lazy and did not hunt down my A/C thermometer, and just aimed an IR thermometer at the vents; that's why my readings are a bit elevated.

A bit more fiddling today disclosed the following findings: With the fan on the lowest setting, all vents, and the seat AC blows cool. As I raise the fan speed, by the time on three bars, the left vent is blowing warm, and the seat AC has stopped. Still blowing nice and cool out the center vents on three bars. As I raise the can a little more, the left center vent gets a little warmer, but the right center vent stays cool.

Update:

The problem with my car turned out to be a defective heater control valve. This is located on the driver's side frame rail. There are a couple of solenoids that control flow independently to the left and right side of the car, and the one that controls the driver's side was stuck in the open position. Once this was replaced, all was good.