My defroster was stuck which was due to a vacuum leak. The leak was in the small vacuum line that passes by the transmission dipstick handle. The embossed letters "TRANSMISSION" on the handle has sharp corners and over time wore a hole in the vacuum line where it touched. It was just by luck I found the leak as it was on the hidden backside of the hose. I felt it but never saw it. I taped over it and worked again. Maybe this will save someone time and a headache.
Thanks for the explanation. I drove for two hours last night with the windshield wipers on, because the cold air shooting onto the inner windshield caused the outside of the windshield to frost over, so i couldn't see. The whole time my wife was running her mouth about not being able to see on her side...Not a pretty scene
If you are ever in the Pasadena, Tx area I'll buy the beer! Your video solved my problem! I was thinking the worst but your video sovled my problem. THANK YOU SO MUCH!
I wish I would have seen this video before I started taking things apart. But thanks for posting this definitely saved me an hour or two of head scratching.
Thank you. I had/have the same problem. I fixed the one leak on that little hose and it worked fine for about 3 weeks, then it stopped working again. I checked the lines again and found a loose connection on one of the hoses so I pushed it back on and tie-wrapped it. I thought that should take care of that but nope, it didn't work. I think it may be that little valve your talking about. I'll check the one I have on there and replace it if need to. Thanks. Good job.
My dash is well broken...... so I don't have to take it apart....... Thanks for posting the video!!! Its a starting point!! Out of 1 million wonders I finally have a starting point!!!
Dude by far the very best eryday normal guy video ever !!!!! Not only did u fix my vent issue ifn any one else wants to post how to fix something they can use this video of urs to guide them on how a to do video is supposed to be done THANK YOU
Thank you I knew it was vacuum control but thought I had a bad control head. Sometimes I can cut the air on and off several times and it'll blow right. Gonna check the lines out
I just found that on my truck, that black line had fallen onto the turbo, melting it apart. Sure enough, my vent and AC are only coming out the defrost setting. THANKS for this video!
Dude I appreciate this I found my leak on accident and broke the hose took off what was broken and manage to use what was still left of the hose and fixed my air now it blows on feet face or defrost
Where does that vacuum line going threw the fire wall connect on the inside?? Mine not connected and trying to run new line but have no idea where it goes
Thanks for a very good video, about too completely redo my HVAC system in my 97 Ram, I also want and will test before I reinstall the dashboard. Thanks 👍
My 2006 Ram 4.7 defrost won’t work when I set it to defrost air the air rushes down to the floor vents and very little to windshield almost nothing at all. Wonder if I could be having same issue.
Very helpful. I have subscribed to your channel. I am about to remove and replace my dashboard. I am going to replace the cruise control plastic line because mine is broken right at the dashboard. I am going to be testing everything while I am in there to make sure the doors, check valves and actuators are working before I install the new dashboard. Do you know how much plastic line I need and the exact diameter? I can figure it out once I get the old dash out, but I thought I would ask. Also, what else might I want to check and replace while I have the dashboard out? I have a 1997, 5.2L Laramie with 285,00 miles on it. It runs great and I have just finished a lot of rebuild on the body and interior. Its very clean and I plan on keeping it forever. I am the original owner, too.
Thanks for the vid, my ram only blows out the defroster and I kept looking at those same lines in the engine compartment wondering what they were for cause they kept falling out of each other
thank you great information I was having same problem and after watching this video am just did the conexion.line without remove all dashboard very helpful
Hi, I have a 1998 Dodge B3500 with an issue similar but mine only goes to defrost when giving it more throttle when going up a hill. I am planning on installing a canaster and a check valve so when I go up a hill and the engine uses up all the vacuum I would still have a reserve in the canister. My issue is which and where the vacuum line I need to tap into is.
I watched your video and solve the same problem with my 99 Dodge, Cummins. The vacuum line comes from the drivers side to the firewall, then to the passenger side. Thank you!
Is this the same basic fix for a 2001 Dodge Durango with the 5.9? Could it also be a similar fix for the rear heat/ac only blowing cool air or is that a blend door issue, or is that maybe something else?
I'm having this same problem on my 04 Dakota. First problem was it was blowing resistors. Changed that, worked for awhile, then stopped again. Wiring was fried in spots, so got new wiring harness and changed that. Worked for awhile, then same issue again. Replaced the motor, and new resistor, same problem. After researching forums and CZcams, found that it's possibly my ignition switch. Will replace that, but I assume, it will not fix this issue. Question is, do I have to take the entire dash out to fix the "doors". If that's the case, I will have to have another vehicle to drive, since this looks like it will be a weekend job to fix it. Thanks for the video.
I'll keep this in mind. Wishing I knew when I had the AC clutch engaging to check. Used a bypass switch on the low pressure cutoff switch so I could refill the system. At best got a ~20°F decrease in temp in the front vent with the dash manual shutters closed other than the center where I had the thermometer. For some reason when I went to switch the bypass switch out and plug in the connector to the new low pressure cutoff switch... the clutch decided it's no engaging anymore. Checked my voltage at the relay and was having strange readings where I'm not sure the logic where the relay coil was and wasn't showing ~13.8V. Same goes with the relay switched female terminals and similar with showing same voltage reading at the AC clutch connector. AC clutch is showing ~4.2Ohms resistance. Computer or maybe the High Pressure switch is triggering since something to do with when filling with AC Avalanche R134a? I tested the high pressure cutoff switch to see if open... though maybe it's opposite of the low pressure switch and needs to be open I was thinking from the heat I guess... so didn't bother jumpering that female connector with the bypass switch. Thinking can try next or maybe needs to sit since computer didn't like what I did and just shut down the system.
Thanks for sharing too! Mine's a 2001 with the 5.9L and I've not used the AC in more than a decade. Was told the AC clutch and no leaks at the time in the systems found... though that shop closed and I never got around to looking into myself. Finally taking the time to diagnose and learn the AC system since planning to rebuilt the whole truck in the future.
Great video..i got a 98 Dodge 3500. my issue is i got a lil heat and i can turn the fan on hi. and i can hear it Kicking full blast. but nit coming outa the vents nowhere.
99 Dakota slt ext cab 5.2l 4x4. What all does vacuum do on these trucks? I have the stuck on defrost issue plus occasional "funny" shifts from the trans, and, somewhat low power from the engine. No fault/check engine light and when my son used his scanner he saw no codes. Could vacuum problem cause all 3 symptoms? ..... Just bought it and the previous owner supposedly barely drove it for the 2-3 years they had it. Of course new gas helps and I did add fuel injector cleaner to one tank full, the more I drive it, 500+ miles so far, there are small signs of improvement. Oh yeah, it has 207,000 miles on it.
I have a 2006 dodge ram 1500 hemi that'll blow air softly and hard but stuck on defrost and heat. I can turn the other knobs but nothing happens and my buttons that light up for max ac and rear defrost no longer light up. Do I just have to replace the module or is there more work involved
Please help I tried taking dash off but must of pulled off a ground some where and cant find it gauges and radio quit working i taped in to ground on radio and can get it to work when i ground out the radio but cant get gauges to work please help any grounds that im not seeing that u can help me with
Thanks for the video you helped me find the problem it is a crack in the vacuum hose between the little circle thing and where it goes into the cab so what should I do now?
You will have to trim off the vac line at the break and relocate the rubbery part to the remaining part of the line. Sometimes there is a small piece of the line broken off in the rubber part. You will have to extract that part before attaching to the remaining part of the line.
Definitely sounds like a vacuum leak. Check the vacuum line near the manifold, into the firewall. This line continues to the switch inside the truck. Either your line is cracked, or the check valve is bad. Not a hard fix at all.
So can anyone point me in the correct direction.. When I turn the ac controls to blow just trough the front it still blow to the floor half way so I barely get air blowing from the top front vents.. What's actually hapenning..?
My problem is my 2001 1500 Dodge Ram AC blows as it should until I accelerate and then I can hear the door move and it starts blowing out of the defrost. When I take my foot off of the gas the inertia will close the door so it closes and air then comes out of the AC from panels. So, they blow out of the front panels until I accelerate then it blows through the defrost until I take my foot off of the gas. This has happened since I bought the vehicle new in 2001.
Part number for check valve? Replaced once on my 98 but only lasted about a week which I bought a cheap valve online probably not rated for this type of use Also mine has 1/8 inch hoses
"Dorman 47170 HVAC Control Vacuum Check Valve" is the one I used in this video. Amazon Link: www.amazon.com/gp/product/B00HE1FRX8/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 Also, all vacuum hoses on the Second Generation Dodge Ram pickup trucks, (1994-2002 model years), are 1/8". Hope this helps. Feel free to post any comments, or questions, for the benefit of all. Knowledge is the river of information benefiting all who drink from it. DG.
When I throttle over 2000 rpm I hear a door in the dash open and close . My ac is running but not blowing when this happens. Is this the same vacuum line causing the problems? I've replaced all ac components under the hood. Condenser, compressor, lines, etc, etc . Had it recharged and balanced at a AC shop. I'm going to replace the dash because it is cracked and want to fix this problem before I put on the new dash. I also replaced the vacuum check valves . Any input would be great. Thx
I had same issues and check valves were bad the vacuum line by the fire wall was cracked and the elbow that goes to the cruise control was cracked. Replaced all the vacuum lines in the engine bay up to fire wall and problem sloved
Anyone help me out I changed the check valve but when I go to merge onto the freeway and I go half throttle the screen bypasses to defrost anyone have this issue and fixed it?
My defroster was stuck which was due to a vacuum leak. The leak was in the small vacuum line that passes by the transmission dipstick handle. The embossed letters "TRANSMISSION" on the handle has sharp corners and over time wore a hole in the vacuum line where it touched. It was just by luck I found the leak as it was on the hidden backside of the hose. I felt it but never saw it. I taped over it and worked again. Maybe this will save someone time and a headache.
That's the line the guys trying to point out but the camera so shaky you wouldn't know it.
Very helpful and straight forward. Finally a video thats not just some guy saying the same things over and over for 10 mins lol
Thanks for the explanation. I drove for two hours last night with the windshield wipers on, because the cold air shooting onto the inner windshield caused the outside of the windshield to frost over, so i couldn't see. The whole time my wife was running her mouth about not being able to see on her side...Not a pretty scene
i have the same issue, drive me nuts
Thank you for solving a horrific problem if I had to pull the dash which I wont.
You are a top workshop warrior.
Thanks you.
Man,.. thanks a lot! After your video I was able to repair my ac in one minute! Thanks !
If you are ever in the Pasadena, Tx area I'll buy the beer! Your video solved my problem! I was thinking the worst but your video sovled my problem. THANK YOU SO MUCH!
This vid just turned an hours long troubleshooting headache for me into a literal 2 minute fix, thank you so much.
I wish I would have seen this video before I started taking things apart. But thanks for posting this definitely saved me an hour or two of head scratching.
Thank you. I had/have the same problem. I fixed the one leak on that little hose and it worked fine for about 3 weeks, then it stopped working again. I checked the lines again and found a loose connection on one of the hoses so I pushed it back on and tie-wrapped it. I thought that should take care of that but nope, it didn't work. I think it may be that little valve your talking about. I'll check the one I have on there and replace it if need to. Thanks. Good job.
My dash is well broken...... so I don't have to take it apart....... Thanks for posting the video!!! Its a starting point!! Out of 1 million wonders I finally have a starting point!!!
Dude by far the very best eryday normal guy video ever !!!!! Not only did u fix my vent issue ifn any one else wants to post how to fix something they can use this video of urs to guide them on how a to do video is supposed to be done THANK YOU
thank you! super clean video.
Thank you
I knew it was vacuum control but thought I had a bad control head. Sometimes I can cut the air on and off several times and it'll blow right. Gonna check the lines out
Thanks for the info. I know where to start now. Very helpful!! And to the point!! Thank you!!!
I just found that on my truck, that black line had fallen onto the turbo, melting it apart. Sure enough, my vent and AC are only coming out the defrost setting. THANKS for this video!
Thank you very much ,this was very helpful.
Very helpful video. I will be using it to address the same issue with my 2001 1500 Ram.👍
Dude I appreciate this I found my leak on accident and broke the hose took off what was broken and manage to use what was still left of the hose and fixed my air now it blows on feet face or defrost
Thanks, right to the point!
Appreciate the video very helpful do make more vids
Excellent video to the point and no bullshitting for 20 min 👍
Where does that vacuum line going threw the fire wall connect on the inside?? Mine not connected and trying to run new line but have no idea where it goes
Great video!👍
Thanks for a very good video, about too completely redo my HVAC system in my 97 Ram, I also want and will test before I reinstall the dashboard. Thanks 👍
Good presentation thanks
so after that black plastic vacuum line comes through the firewall on the right side of the truck, where is the first place it goes and attaches?
that was a big help thanks
I needed this thanks. Should the air be going to, or from the intake manifold?
Nice video! Good job!
You are the man!!!!!
Very useful! Been searching why my ac wouldn’t work
My little vacuume line was broke too,only had defrost....not any more..👍🏿
Any ideas on where to obtain a air conditioning plenum box for 2001 dodge ram 1500?
My 2006 Ram 4.7 defrost won’t work when I set it to defrost air the air rushes down to the floor vents and very little to windshield almost nothing at all. Wonder if I could be having same issue.
So should the recirc door be closed to recirculate the air in vehicle or open
Very helpful. I have subscribed to your channel. I am about to remove and replace my dashboard. I am going to replace the cruise control plastic line because mine is broken right at the dashboard. I am going to be testing everything while I am in there to make sure the doors, check valves and actuators are working before I install the new dashboard. Do you know how much plastic line I need and the exact diameter? I can figure it out once I get the old dash out, but I thought I would ask. Also, what else might I want to check and replace while I have the dashboard out? I have a 1997, 5.2L Laramie with 285,00 miles on it. It runs great and I have just finished a lot of rebuild on the body and interior. Its very clean and I plan on keeping it forever. I am the original owner, too.
Thanks for the vid, my ram only blows out the defroster and I kept looking at those same lines in the engine compartment wondering what they were for cause they kept falling out of each other
thank you great information I was having same problem and after watching this video am just did the conexion.line without remove all dashboard very helpful
Good video, thanks 👍👍
How about the vacuum hose on the other side of the engine I have the red hose that disconnected and can't find where it goes
Having this issue with my 99 van I think it's a little more complicated any advice would be great
Hi, I have a 1998 Dodge B3500 with an issue similar but mine only goes to defrost when giving it more throttle when going up a hill.
I am planning on installing a canaster and a check valve so when I go up a hill and the engine uses up all the vacuum I would still have a reserve in the canister.
My issue is which and where the vacuum line I need to tap into is.
On my 2001 ram 3500 I found the valve line was broken. I replaced the hose but still same problem. Ac blows only at windshield like before.
I watched your video and solve the same problem with my 99 Dodge, Cummins. The vacuum line comes from the drivers side to the firewall, then to the passenger side.
Thank you!
Thank you good video
Great video
Is this the same basic fix for a 2001 Dodge Durango with the 5.9? Could it also be a similar fix for the rear heat/ac only blowing cool air or is that a blend door issue, or is that maybe something else?
That line broke on my 2000 2500 diesel dose that line go into the hvac box? I ordered a new one from mopar today thanks!
Same problem & fixed it in 10 seconds by clipping bad part & sliding it back in rubber piece
Part number on check valve or will any one way check valve work ?
I'm having this same problem on my 04 Dakota. First problem was it was blowing resistors. Changed that, worked for awhile, then stopped again. Wiring was fried in spots, so got new wiring harness and changed that. Worked for awhile, then same issue again. Replaced the motor, and new resistor, same problem. After researching forums and CZcams, found that it's possibly my ignition switch. Will replace that, but I assume, it will not fix this issue. Question is, do I have to take the entire dash out to fix the "doors". If that's the case, I will have to have another vehicle to drive, since this looks like it will be a weekend job to fix it. Thanks for the video.
I'll keep this in mind. Wishing I knew when I had the AC clutch engaging to check. Used a bypass switch on the low pressure cutoff switch so I could refill the system. At best got a ~20°F decrease in temp in the front vent with the dash manual shutters closed other than the center where I had the thermometer. For some reason when I went to switch the bypass switch out and plug in the connector to the new low pressure cutoff switch... the clutch decided it's no engaging anymore. Checked my voltage at the relay and was having strange readings where I'm not sure the logic where the relay coil was and wasn't showing ~13.8V. Same goes with the relay switched female terminals and similar with showing same voltage reading at the AC clutch connector. AC clutch is showing ~4.2Ohms resistance. Computer or maybe the High Pressure switch is triggering since something to do with when filling with AC Avalanche R134a? I tested the high pressure cutoff switch to see if open... though maybe it's opposite of the low pressure switch and needs to be open I was thinking from the heat I guess... so didn't bother jumpering that female connector with the bypass switch. Thinking can try next or maybe needs to sit since computer didn't like what I did and just shut down the system.
Thanks for sharing too! Mine's a 2001 with the 5.9L and I've not used the AC in more than a decade. Was told the AC clutch and no leaks at the time in the systems found... though that shop closed and I never got around to looking into myself. Finally taking the time to diagnose and learn the AC system since planning to rebuilt the whole truck in the future.
Great video..i got a 98 Dodge 3500.
my issue is i got a lil heat and i can turn the fan on hi. and i can hear it Kicking full blast. but nit coming outa the vents nowhere.
99 Dakota slt ext cab 5.2l 4x4. What all does vacuum do on these trucks? I have the stuck on defrost issue plus occasional "funny" shifts from the trans, and, somewhat low power from the engine. No fault/check engine light and when my son used his scanner he saw no codes. Could vacuum problem cause all 3 symptoms? ..... Just bought it and the previous owner supposedly barely drove it for the 2-3 years they had it. Of course new gas helps and I did add fuel injector cleaner to one tank full, the more I drive it, 500+ miles so far, there are small signs of improvement. Oh yeah, it has 207,000 miles on it.
Where does the vacuum line from the engine bay connect to on the inside of the cab??? Someone help! Lol awesome video too!
I have the dash pulled out on a 06 dodge 1500. Trying to test actuators. What all has to be plugged in for the truck to still start
I have a 2006 dodge ram 1500 hemi that'll blow air softly and hard but stuck on defrost and heat. I can turn the other knobs but nothing happens and my buttons that light up for max ac and rear defrost no longer light up. Do I just have to replace the module or is there more work involved
thanx for this video
I am having this same exact problem with my 1997 Dodge Ram Van, Makes for a very Hot situation in the summer
Thank you
Would this work on a 99 Dakota? Have been looking around for something of substance and nothing comes up.
Where did you find the check valve
2000 Ram 1500 blowing cold AC hard out the floor vents and not so hard out the top vents. What could the possible cause be?
What is this part called exactly? Trying to order it from autozone and can’t find it.
Thank you! This cover's my problem
Wish I could buy you a beer my friend. Cut it while installing new oil pressure sensor. All good now many thanks.
MattyP’s Universe do you have to disassemble the dash to change that vacuum line?
I have the same problem. I'm going to check the vacuum line under the hood and go from there
I have a '99 Dodge ram when my truck holding still it comes out to the vent when I take off it goes out through the defrost
do you have to take the dash down to make the repair
Got the same thing...air comes from defrost good but switch to vent and it's very faint..
Please help I tried taking dash off but must of pulled off a ground some where and cant find it gauges and radio quit working i taped in to ground on radio and can get it to work when i ground out the radio but cant get gauges to work please help any grounds that im not seeing that u can help me with
What if it only comes out the top when you press the gas?
How do I get my ring out of the front defrost
Good stuff. Short and sweet, good info. But please hold the camera steadier!
Can I assume the same on my 2002 dodge ram 1500 4.7l?
Where does the vacuum like run too
Good video 👍. Only question is since i have that issue now, how do i fix the line without having to remove the entire dash? It blows defrost only.
J Tizzle I’ve got the same problem did u get it fixed ?
Thanks for the video you helped me find the problem it is a crack in the vacuum hose between the little circle thing and where it goes into the cab so what should I do now?
You will have to trim off the vac line at the break and relocate the rubbery part to the remaining part of the line. Sometimes there is a small piece of the line broken off in the rubber part. You will have to extract that part before attaching to the remaining part of the line.
2001 Dodge Ram 1500 when going up hill/over pass a/c comes out defrost area...once level changes back to regular vents....would this fix issue?
Definitely sounds like a vacuum leak. Check the vacuum line near the manifold, into the firewall. This line continues to the switch inside the truck. Either your line is cracked, or the check valve is bad. Not a hard fix at all.
Have the same problem did what you did but could not get the door vent open
Great video! What controls the heat/cold? My truck has great cold and no heat.
Sounds like your heater core may be clogged, try back flushing first and also change your thermostat. .... if that doesn't work you may need a new one
Do I have to take apart my dash like that to fix it or?..
How much does something like this cost I’m having trouble with my ram
So can anyone point me in the correct direction.. When I turn the ac controls to blow just trough the front it still blow to the floor half way so I barely get air blowing from the top front vents.. What's actually hapenning..?
My truck does the same thing but only when I accelerate hard. A/c blows from front to defrost vent.
My problem is my 2001 1500 Dodge Ram AC blows as it should until I accelerate and then I can hear the door move and it starts blowing out of the defrost. When I take my foot off of the gas the inertia will close the door so it closes and air then comes out of the AC from panels. So, they blow out of the front panels until I accelerate then it blows through the defrost until I take my foot off of the gas. This has happened since I bought the vehicle new in 2001.
Did you ever figure this out? I am still having the same issue.
@@blakewalker566 Yes, with mine it was the suction from the Vacuum lines.
Man i couldnt see anything, can you show the parts in the engine again please
I have a 98 ram 5.2 and my air only comes out in defrost. I am going to try this
I have a 98 dodge ram doing the same thing I just got a new control switch maybe I just need to check that first .help
My truck has same exact problem where can I get the parts tho
Hold the camera steady so we can see the vacuum conditions better since there are 2 ✓ valves..
Part number for check valve? Replaced once on my 98 but only lasted about a week which I bought a cheap valve online probably not rated for this type of use
Also mine has 1/8 inch hoses
"Dorman 47170 HVAC Control Vacuum Check Valve" is the one I used in this video.
Amazon Link: www.amazon.com/gp/product/B00HE1FRX8/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Also, all vacuum hoses on the Second Generation Dodge Ram pickup trucks, (1994-2002 model years), are 1/8".
Hope this helps. Feel free to post any comments, or questions, for the benefit of all.
Knowledge is the river of information benefiting all who drink from it. DG.
Can it be fixed without pulling the dash?
Same problem with a 98 Ram 1500 v6. I will try that.
When I throttle over 2000 rpm I hear a door in the dash open and close . My ac is running but not blowing when this happens. Is this the same vacuum line causing the problems? I've replaced all ac components under the hood. Condenser, compressor, lines, etc, etc . Had it recharged and balanced at a AC shop. I'm going to replace the dash because it is cracked and want to fix this problem before I put on the new dash. I also replaced the vacuum check valves . Any input would be great. Thx
I had same issues and check valves were bad the vacuum line by the fire wall was cracked and the elbow that goes to the cruise control was cracked. Replaced all the vacuum lines in the engine bay up to fire wall and problem sloved
My vacuum line has come loose inside the dash where it connects to the 4 vacuum line connector and I can’t figure out where it goes
The vacuum line coming from the firewall connects to the panel/defrost door actuator. Hope this helps. Feel free to ask, or comment, anytime.
and not to be funny but at a stand still. i got heat. i start drivng ans cold air. can you help
the doors on my dodge 99 open at idle and slowly driving, when i get on the highway or accelerate hard it closes the front and blows out defrost 😨
Mine did the same thing. It was the hose that he pointed out. I bought a vacuum line repair kit at AutoZone and fixed the line. Good to go.
Anyone help me out I changed the check valve but when I go to merge onto the freeway and I go half throttle the screen bypasses to defrost anyone have this issue and fixed it?
and i finally figure what with this ancient truck....previous owner cut the line for reason beyond my understanding