98 Dodge Ram, 4x4, 8.0, auto.

The a/c in my truck just isn't performing as well as it should. I have had the system recharged (twice... due to a leak) some lines replaced, and according to the shop that did the work, they system is 'operating as intended'. Well, so much for my opinion of their ability. It's been in the high 80's, low 90's here of late, so, a/c would be really nice. Problem I have is, the air temp at the outlets is barely cooler than the outside air. The system is supposedly fully charged, but, performance is terrible. Before taking it back to them for a third time..... I want to adjust the blend door. I know there is a procedure for this, and it is probably even posted here somewhere, but, I simply can't find it. Can't find it in the service manual either...... Anyone have any clue?

 

No clue on an adjustment procedure for the blend door, however, based on the symptoms, it sounds like something is wrong with the A/C system when you're getting nearly warm air at the inside air ducts. Did the shop that did the work provide any indication of what the high and low gauges read when they completed their A/C system work or determine what the temperature was of the air coming out of the inside air ducts with the A/C running on max?

 

No. They were amazingly uninformative. In reality, I don't think they even bothered to check outlet temps...... well, maybe stick their hand in there to feel it.... Maybe... Looking at the performance chart in the FSM though, no way on god's little green acre is the system performance anywhere near what it should be. Even with 90 degree outside temps, I should see outlet temps in the low 60's, high 50's. It ain't even close.

I suspect that their techs simply don't have a clue what they are really doing. Or, are extremely lazy.... Put it on the a/c machine that does everything by itself, and call it 'fixed'...... I am going to find a different shop, theses guys troubleshooting skills leave a lot to be desired.

 

I'm (quite obviously) not an A/C person, so forgive the lack of terminology knowledge while I speak in layman's terms (or more likely, like a 3-year-old would say it)....

Can you hear your compressor "click on" when it should be cooling? I had a similar issue (although I hadn't had any work done on it) many moons ago: fully charged, blowing, but not cooling. When I took it in for a transmission replacement (rebuilt), I had some issues with the shop's lack of communication (work was fine). As part of customer service, the shop fixed my A/C for free by simply putting a shim in wherever the compressor (clutch?) gets engaged - all the moving parts of the system were moving, but the compressor was just not getting engaged properly because something was not pulling it out far enough. (Told you it would be like I was a 3-year-old speaking.)

That was between 8 and 9 years ago, and I've had ice cold A/C ever since.

 

This vid is GREAT, jump to 13:00ish if you want.

 

That's exactly what I said, isn't it?

 

Compressor was new when I bought the truck, but, I never bothered with a/c, until the truck was in the shop for another reason. According to the shop, pressures are good, and the system is 'functioning as intended'...... I have a bit of a different opinion on that than they do apparently..... Thing is, I don't know if the blend door is closing completely, and would like to make sure that is correct before I take it back to them, yet again......

 

Why not just disconn the cable on top of box behind glove box and "thunk" it around by hand?

You should be able to get a pretty good feel instinctually...

 

May have to resort to that. Need to check and see that the cable is still secured to its mount in any event......

 

What year 2nd gen trucks started using the motorized unit to open/close the blend door?