3rd Gen Blend Door issue. Grab a club cause we are beating this dead horse!

[Big_Horn]

OK, This ones weird. So I know about the blend door issue. But this one is throwing me off. Its been a little warm in the NW, and I was running my AC. I get cold air with the 2 drivers vents, but warm/hot air in the passenger vents. Now the wife doesn't know this but when she does she's gonna be PISSED! she likes her AC and if its not fixed, I'm banished to the shotgun position, in the sweltering, blowing hot heat. Even with this issue I can only get half the cooling since I am blowing hot air on one side, then cold air on the other. Has anyone else experienced this or know the fix? My guess is a dash pull is in my near future. If it is suggested, who has the most recommended blend door fix?

 

[Big_Horn]

I found this, still reading it...

https://www.turbodieselregister.com...ct-opening-the-ac-relief.258779/#post-2511402

 

[FOXY005]

I have an "03" don't know what year yours is or if it it is different. On mine the system is zoned as to top of the coil and bottom of the coil so a low refrigerant charge in the system will deliver cold air to one side and warm air to the other. That is because the top of the coil feeds the vents on the passenger side and since the charge is low only the bottom of the coil gets cold. You will also notice with this condition that the coil will in very humid weather ice over and you will notice a big decrease in the drivers side cold air flow, turning the system off for about 10 minutes and allowing it to defrost will restore the cold air to the drivers side. So my suggestion would to be check your refrigerant charge.

 

[p-Bar]

My 04.5 does the same thing . I know all the doors are wasted

 

[jgillott]

Many will recommend the Heater Treater doors. They are very high quality units but come with a price. I have had really good luck with the newer Mopar replacements. They upgraded the doors at some point over the years and they seem to be a little more reliable.

 

[Big_Horn]

@FOXY005, I guess I neglected to mention the year... I thought I made a footer with the specs and didn't. I have an 06. I read the article a few times trying to digest what @Tuesdak was saying. I have not noticed any blend door issues as of yet. I guess there may be a chance that only one side of the blend door broke but there is no drop in air flow to the passenger side, only a temperature difference. There are some great videos on pulling the dash and HVAC box out and replacing to doors but I think my first step will be a evac. and recharge of the AC before I go down the blend door route. Reading the article in depth, it makes more sense. I noticed late spring and into this summer that my fan clutch has been activating more and more often. On cold start up, during low ECT values... etc. The article does cover weird fan clutch triggers. I had the AC compressor replaced 2 years ago, this was done at the dealership. (don't beat me up too much on that decision, my hands were tied) So I know its newer, but hey it could be going bad too. IDK... damn gremlins.

 

[GrantP]

I played this game for years on my 06, the problem was always low refrigerant. It was an annual event. The compressor failed a few years ago and I literally replaced everything in the system and haven't had a problem since.

As mentioned above, check your refrigerant level before you start digging into blend doors.

 

[Big_Horn]

@GrantP I totally agree.

 

[Tuesdak]

Quick and dirty way to tell if the AC is "low" is to feel the evaporator inlet and outlet pipes at the cab firewall. They both should be cold and near the same cold with the compressor running a few min and fan on high. Cold and warm is nearly empty of refrigerant. Avoid the hot heater pipes on a hot engine when doing this so a cold engine is safest test time for this.

If you have cold and warm pipes you found the problem. The warm pipe extends that warm to the top half of the evaporator. Others above explain the airflow temp difference. The sticker for refrigerant charge weight is more or less determined by the evaporator being full of liquid refrigerant. This is why both evaporator pipes should be near same cold feeling.

The in depth book I wrote linked above explains why these systems loose half their refrigerant now and then even when they were brand new without a leak.

Note on freeze up: just turn the AC button off with the fan on high - it will defrost quickly... well out in AZ anyway.

 

[WesJohnston]

I had the same problem on my ‘03... only my wife knew the problem and yes, she was not happy. I pulled the dash and installed pricey Blend Door USA doors. NONE of my OEM doors were broken but figured I would replace them with bulletproof doors since it was apart. Also checked all the actuators and they function flawlessly. It’s raining right now and I will finish putting the dash back together when it quits. Unfortunately I got sidetracked with a parasitic draw issue. I wish I had read this thread BEFORE I made the assumption I had a broken blend door. Bottom line... charge your AC system, I wish I had (like my better half suggested in the first place ).

 

[sag2]

Warmer on passenger side is almost always low refrigerant.

 

[cerberusiam]

Have the charge checked and probably should go ahead and replace the accumulator also. Check your condenser, if it has bent fins replace it. If you think the blen doors are bad forget heater treater, they are junk. You want the whole set form Blend Door USA and replace the evaporator in the HVAC box. Do all that and then you will have to turn it DOWN so wife doesn't need a sweater.

 

[Big_Horn]

This is great info fellas!! I will get the AC done and report on my findings. THANK YOU ALL for commenting! This is priceless information!

 

[Big_Horn]

So I had the evac and recharge done today. They said that the system was nearly empty. Recharged, Started the truck and within 1 minute ran the AC on high. Popped the relief valve and dumped the system. He refilled the system and said good luck... kinda back to square one. On my way home I cycled the AC on the freeway after about 5 minutes of engine running and had cold air for about 20 minutes until I turned everything off.

 

[jgillott]

So I had the evac and recharge done today. They said that the system was nearly empty. Recharged, Started the truck and within 1 minute ran the AC on high. Popped the relief valve and dumped the system. He refilled the system and said good luck... kinda back to square one. On my way home I cycled the AC on the freeway after about 5 minutes of engine running and had cold air for about 20 minutes until I turned everything off.

How did they charge your system? Machine?

 

[Big_Horn]

How did they charge your system? Machine?

Yes, professional shop

 

[jgillott]

Did they tell you if they ran a leak test?

 

[Big_Horn]

No I dont think they did one... He did put dye in the system though...

 

[Big_Horn]

Well... Looks like I am back to square one. So after the evac/recharge, things seemed to be running well. no more weird clutch fan activations, actually I do not recall it ever turning on at all one this was done. Today while loading up the truck to go to working (defrost on not AC) idling for about 5 minutes or so, the relief valve popped dumping all the R134a in a plumb of smoke. I tried re-charging the system with the off the shelf cans and once it received the R134a, it started venting again. Fan never came on at idle. watching the guage on the can, the low pressure side climbed to 100psi before unplugged it out of fear. So I am at a bit of a loss and really want to get this fixed. I have a trip to Arizona planned in November, and I do run the defrost nearly all the time at home. I am looking for some direction from the group and hope that this thread hits the TDR publication. I am actually surprised that it hasn't made it yet.

 

[seafish]

Many will recommend the Heater Treater doors. They are very high quality units but come with a price. I have had really good luck with the newer Mopar replacements. They upgraded the doors at some point over the years and they seem to be a little more reliable.

While true that the Heater Treater doors were the first aftermarket upgrade to the Mopar doors, since their release Blend Door USA is making an even better fit and finish doors then the HT ones.

TDR member, Flopster843 did a comsparison/review of them and its pretty much a no brainer to go with the BlendDoor ones.

https://www.turbodieselregister.com/threads/heater-treater-vs-blend-door-usa-pic-heavy.255207/