Chevy and GMC Duramax Diesel Forum banner
  • Hey Everyone! Enter your ride HERE to be a part of this months Ride of the Month Challenge!
1 - 15 of 15 Posts

·
Registered
2007 LBZ!
Joined
·
16 Posts
Discussion Starter · #1 ·
Ac was not working so put the truck in the shop.
First trip to the shop…..
-went to recharge it and found issues. They replaced the orifice tube, and condenser with a full charge($550). A/c was cold cold! On the 3 mile drive home had to turn it down cuz it was so cold (4 miles from the shop). First day casually drove to and from work ac worked great! (It was about 80 degrees). Second day casually drove to work(didn’t need ac) then on the way home did some spirited driving with a heavy foot at times to meet the family for dinner on time. The whole way to meet them (35 minutes and 92 degree outside temps) the ac never got cold, it stayed cool but warm enough it felt better to crack the windows then to run the “a/c”.
Dropped the truck off that night.

-second trip to the shop
They had previously put in dye with the recharge and searched every inch of the truck and couldn’t find a leak! The pulled the refrigerant and said it still had the exact amount they put it. Put fresh in, and said it was ice cold again. And they continued to look for leaks. Kept it overnight. Waited til the hottest point of the day and tested it again and they said it started blowing warm again. Once again had everyone in the shop helping to find a leak. Then they hit me with the best phrase ever! “I really don’t know what it could be, so I’m not gonna charge you anything, I’m sorry”

messed with it in the driveway, and the ac button (the snowflake) the temperature doesn’t change with that on or off,BUT the compressor works like it should when it’s pressed.
so I’m stuck. Anyone have any ideas or experiences?!?!?!
 

·
Registered
2003 GMC 2500HD 4x4 Banks Super Scoop, Banks Rear Dif Cover, Mechman 320A alternator, S&B fuel tank
Joined
·
107 Posts
Could be your heater blend door. They will stick and essentially you are using your heater.
It can be an intermittent problem, it sticks, then sorts itself out after things are shutdown.
It will throw a code, I don't recall what it is though.
 

·
Registered
2007 LBZ!
Joined
·
16 Posts
Discussion Starter · #3 ·
Could be your heater blend door. They will stick and essentially you are using your heater.
It can be an intermittent problem, it sticks, then sorts itself out after things are shutdown.
It will throw a code, I don't recall what it is though.
I thought the same thing, but everything I read said it would be like hot on one side an cool on the other, this is cool but not cold across the whole dash vs being different on each side
 

·
Registered
2003 GMC 2500HD 4x4 Banks Super Scoop, Banks Rear Dif Cover, Mechman 320A alternator, S&B fuel tank
Joined
·
107 Posts
There are three different blend actuators. One is the "main" the other two are for the driver.and passenger side respectively.
If one of the "side" ones goes out then you get the hot one side, cold the other situation.
If the main one goes you get symptoms like you have.
The good news is that it also the easiest to get to, it is right up under the passenger dashboard, ike 6 screws total.
 

·
Registered
2003 GMC 2500HD 4x4 Banks Super Scoop, Banks Rear Dif Cover, Mechman 320A alternator, S&B fuel tank
Joined
·
107 Posts
Here's a video of the process on a suburban, but it's the same on the pickups.
Remember you have to calibrate it afterwards. There are several videos on that, and make sure the power is OFF before you start or it will damage the unit.

 

·
Registered
2007 LBZ!
Joined
·
16 Posts
Discussion Starter · #6 ·
There are three different blend actuators. One is the "main" the other two are for the driver.and passenger side respectively.
If one of the "side" ones goes out then you get the hot one side, cold the other situation.
If the main one goes you get symptoms like you have.
The good news is that it also the easiest to get to, it is right up under the passenger dashboard, ike 6 screws total.
Awesome! I will try that! Thank you!!!
 
  • Like
Reactions: Shadowgrouse

·
Registered
2007 LBZ!
Joined
·
16 Posts
Discussion Starter · #7 ·
Here's a video of the process on a suburban, but it's the same on the pickups.
Remember you have to calibrate it afterwards. There are several videos on that, and make sure the power is OFF before you start or it will damage the unit.

Just ordered it and will do it as soon as I get home today! And I will update if it works or not! Fingers crossed!!!!
 
  • Like
Reactions: Shadowgrouse

·
Registered
2003 GMC 2500HD 4x4 Banks Super Scoop, Banks Rear Dif Cover, Mechman 320A alternator, S&B fuel tank
Joined
·
107 Posts
Hope that solves the problem!
Don't forget to calibrate it.
 

·
Registered
2007 LBZ!
Joined
·
16 Posts
Discussion Starter · #9 ·
There are three different blend actuators. One is the "main" the other two are for the driver.and passenger side respectively.
If one of the "side" ones goes out then you get the hot one side, cold the other situation.
If the main one goes you get symptoms like you have.
The good news is that it also the easiest to get to, it is right up under the passenger dashboard, ike 6 screws total.
New main blend door actuator, calibrated, and no change unfortunately 😔
 

·
Registered
2003 GMC 2500HD 4x4 Banks Super Scoop, Banks Rear Dif Cover, Mechman 320A alternator, S&B fuel tank
Joined
·
107 Posts
Dang, I'm sorry to hear that.
Hopefully someone else has some ideas.
 

·
Premium Member
Joined
·
3,277 Posts
I assume this is an auto dual zone HVAC system. You say the compressor runs but what are the system pressures? Why was the shop constantly looking for a leak? Sounds like they believed the system pressures were not correct and showing a low state of charge? Can you get full heat out of the vents? Do all modes (vent, floor, defrost) work correctly?
 
  • Like
Reactions: Shadowgrouse

·
Registered
2007 LBZ!
Joined
·
16 Posts
Discussion Starter · #12 ·
I assume this is an auto dual zone HVAC system. You say the compressor runs but what are the system pressures? Why was the shop constantly looking for a leak? Sounds like they believed the system pressures were not correct and showing a low state of charge? Can you get full heat out of the vents? Do all modes (vent, floor, defrost) work correctly?
Yes sir it is, I’m not sure what the pressures are since the shop did that. There were pressure issues before so they replaced the condenser and orifice tube. Filled it and it was ice cold for two days then went “cool”. They were looking for leaks bc it was odd it was only like that for two days. They told me when they pulled the refrigerant and put fresh in it pulled and reinstalled the exact amount it calls for. Yea full heat works great and I checked all the settings (vent, floor, defrost) yesterday after the actuator change and they are work great
 

·
Registered
2007 LBZ!
Joined
·
16 Posts
Discussion Starter · #13 ·

·
Registered
Joined
·
166 Posts
They replaced my thermostats at the dealership in North Carolina (best dealerships I've ever been to are in the Carolinas). Solved the problem. It was getting stuck on heat or A/C, and I couldn't get it to switch to the other. They diagnosed it and replaced the thermostats for <$200. Wished I would have started with them as I'd spent much more than that at other shops and never got it fixed.
 

·
Registered
2007 LBZ!
Joined
·
16 Posts
Discussion Starter · #15 ·
They replaced my thermostats at the dealership in North Carolina (best dealerships I've ever been to are in the Carolinas). Solved the problem. It was getting stuck on heat or A/C, and I couldn't get it to switch to the other. They diagnosed it and replaced the thermostats for <$200. Wished I would have started with them as I'd spent much more than that at other shops and never got it fixed.
Thanks man! I ended up just saying screw it and dumped money into the whole thing so now I have a new
-main blend door
- condenser
-drier
-compressor
-all lines but one hard line replaced
And $1k later my ac is works better then my wife’s ‘19 escape and holdin strong lol
 
1 - 15 of 15 Posts
Top