Vacuum Lines for Climate Control

2003 DODGE RAM
150,000 MILES • 5.7L • 4WD • AUTOMATIC
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DAISYGIRL8688
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I would like to know where in the engine bay does the vacuum line come into the dash to control the control of the vents.
Can you access it when you remove the radio?
Jun 10, 2022 at 5:35 PM
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JACOBANDNICKOLAS
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Hi,

On vehicles produced with a vacuum-controlled HVAC system, vacuum is supplied directly from the intake manifold. It is fed into the passenger compartment through the firewall.

However, in 2003, the actuators on this vehicle were electric.

Let me know exactly what is happening. Hopefully, I'll be able to help you.

Let me know.

Joe
Jun 10, 2022 at 10:15 PM
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DAISYGIRL8688
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Thanks for the info! This truck has dual slider knob temperature control for the A/C, one for driver and one for passenger. When /AC is on, cold air only comes from driver side (yeah!) but it's warm on the passenger side regardless of the position of the slider knob. I am thinking its a blend door problem, but I don't have ability to remove whole dash. I attempted to remove the panel around the radio to see if I could check the slider potentiometer but was not successful. I also thought if I could remove the panel and if I could reach the door, I could tie it in the open position.

I think the mode selector is not working as I only get air from the top vents but better than no air at all.

Thanks for the help!
Jun 11, 2022 at 12:18 PM
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JACOBANDNICKOLAS
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Hi,

If you look below, I provided the directions for replacement. The first pic shows its location. The remaining pics are the directions. I highlighted the second line which is a bit frustrating. See if you can gain access without removing the entire panel.

Let me know.

Joe

See pics below.
Jun 11, 2022 at 7:59 PM
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DAISYGIRL8688
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Hi,
Thank you very much for the diagrams. This appears to be a quite a long job and requires removing the dash and ac and heater lines. I found these videos which does a good job of showing what has to be done:

https://www.youtube.com/watch?v=dBAtCnIxC2A
https://www.youtube.com/watch?v=_sRvLSDALLc

I guess if you are going this far, you should replace all the doors, given the age of the truck. Usually all hinges on the door are brittle and the foam sealing has rotted away.

Here is a company who makes high quality replacements:
https://www.dieselpowerproducts.com/p-blend-door-usa-complete-hvac-repair-kit-03-09-ram?variant_id=21240&%3Fcampaignid=380196658&adgroupid=1231453211297606&creative&matchtype=e&network=o&device=c&keyword&msclkid=3add30c481fc170ea0625262cc076add

I guess i will defer this project until I get all the parts and have a long weekend.

Jun 12, 2022 at 1:39 PM
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JACOBANDNICKOLAS
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Hi,

Thanks for the info. It will likely help others. As far as the job is concerned, it is a bit of a process; however, it is doable.

If you have a chance, let me know how it turns out for you. Also, let me know if there is anything I can do to help.

Take care,

Joe
Jun 12, 2022 at 8:02 PM
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DAISYGIRL8688
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Joe, thanks for all the help! You guys provide a valuable service for all us DIY guys who are struggling to understand these complicated auto subsystems!
Jun 14, 2022 at 8:36 PM
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JACOBANDNICKOLAS
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You are very welcome. Things just seem to be getting more and more in-depth. Nothing is easy. LOL I miss the old days in many ways. LOL

Take care of yourself and please feel free to come back anytime in the future. You are always welcome.

Joe
Jun 14, 2022 at 9:18 PM
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DAISYGIRL8688
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I'm very old school too, growing up on 60s-70s V8's, mostly small block Chevrolets and Fords. Things that I don't like today is when you lean over the engine nowadays, you cannot see that ground! I cringe whenever I drop a bolt or socket and I don't hear it hitting the ground! Then getting a magnet that sticks to everything as you try to snake it down into the abyss. Along the same line is that I need help from guys like you just to find parts and components, especially sensors! Then even after finding them, I have to remove 2-3 other things to get to it. Just too many darn hoses and wires running all over the place! The car systems are just getting too complicated, and I have trouble figuring out what all those three letter acronyms stand for much less what and how they work. It is getting very nearly to the point where I have to say "uncle" (I have a Prius!). The PCMs and TCMs and their scanners are amazing, though. Kinda fun wading through all the menus and seeing what they do, even though I haven't a clue on many of them. Again, thanks a lot for all the help!
Jun 15, 2022 at 2:37 AM
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JACOBANDNICKOLAS
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Hi,

I totally understand. I had a 15.00 plastic pipe that was three inches long on an Audi A8. It went between the engine block and the oil cooler, and had an o-ring on both ends. Well, the plastic, from age, was deteriorating, and I had no choice but to replace it.

The flat rate for the replacement was (and I'm not making this up) 24 hours. Ugh!! Step 1 in the manual was, "Remove Engine". LOL It was a $15.00 part, but a dealer would have charged nearly $3,000.00 to do it. Of course, I'm too stubborn to do that, so I moved and lifted, and squeezed to do it, but I got it done. LOL And, I did it in 8 hours. LOL

Take care, and I'm here if you have questions. At least I'll try to answer them. LOL

Joe
Jun 15, 2022 at 9:11 PM
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DAISYGIRL8688
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Yep, I feel your pain. I wish aspiring auto engineers' curriculum would include a semester of hands-on practical repair experience at a dealer service shop. I remember seeing a V8 Porsche needing the front tires and splash guards removed just to change plugs. I also saw where replacing knock sensors required the whole top end of a V6 Lexus to be removed.
Take care and thanks for all you guys do!
Jun 16, 2022 at 1:54 PM
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JACOBANDNICKOLAS
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Hi,

You are very welcome. Please feel free to come back anytime. You are always welcome here.

Take good care of yourself.

Joe
Jun 16, 2022 at 9:59 PM