This is not for my truck but my buddy has a 2006 mega cab and all the sudden his a/c is acting funky. He says that the drives side vents are blowing just like normal but the passenger side vents are just bearly blowing (but they are still blowing a little bit)n I've done some searching but and have even found post on here that sound similar but nobodys narrowed it down im not sure if its the recirc door, the blend door, or somthing completely different.

Any help would be appreciated its hot riding shotgun in his truck!!!

 

All of the flow is controlled by the blend doors , the blend doors are controlled by vacuum , so use a vacuum gage to see what is the problem , a disconnected vacuum line , loss of vacuum or the diaphragm in the vacuum motor , oh & the switch on the dash can leak or not transfer vacuum .

 

What year forum is this? There is NO VACUMN on 3rd generation trucks heat/ac system controls.Its all electric.There are issues with blend doors and recir doors.Try using the SEARCH function.Ought to be lots of info and reading.

 

pretty much disreguard everything John Faughn just posted.

 

i had the same issue with my truck, turned out there was a ground wire that was broken and was not allowing one of the doors (blend or recirculate) to not function properly. took the dealer around 3 hrs or so to fix.

 

I noticed on my 06 that more air comes out of the passenger side now. (yes i know all the plumbing comes from the passenger side to the driver) So now i ride around with both passenger vents closed and still have poor circulation coming out of the drivers side. I have watched the motors move when you turn the **** in each selection. I cant figure out what it is.

 

anybody else? also just so I can be clear what is the difference between what
the blend door and the recirc door does? thanks!

 

blend door blends warm air and cold air for temp control,
Recirculation, or fresh air door switches from pulling in air from the outside to just recirculating the cabin air. That is usually the difference between Max A/C and Normal A/C

 

This is kinda off the subject to an extent but here goes. I had a waterpump bearing go out and slung the serpentine belt off. When it did this I had like no brakes I thought our truck had a pump to make vaccum for the brakes?

 

Run off the back of the power steering pump I think.No belt kills it.

 

Had a friend with the same problem turned out just low on freon. System tries to keep the driver happy. Sometimes it's better to keep the wife happy.

 

Ok got the same issue...Wife pregnant and unhappy her side blows warm air my ice cold. She even mentioned the words...God i dont dare say!..MINIVAN!!!!. does enyone know where the blend door is so that i can check it..any diagrams, pictures or guides???.

 

You need to read this thread to understand the problem.
https://www.dieseltruckresource.com/...passenger+side

I had a 15 degree difference between the driver and passenger side and added freon and now there is about a 6 degree difference. I also believe the ac mod thread would help.