Bro you are the only video out here speaks on this, I went under the hood and my line wasn't even connected to that vacuum ball. The air feels beautiful now thank you bro great video
did you have to take the battery out to connect to vacuum ball? i couldn't find the where the hoses are attached to the T but i did find one hose just dangling...when i put my finger over the opening of the hose it has suction...i think this is supposed to be connected to the vacuum ball under the battery?
Thanks very much for this video. I have a 3500 as a family car for my big family, and in Texas the AC is critically important. So I was vexed by the unusual aspect of temporary changes while driving and figured it was some sort of vacuum issue. Your video was very beneficial for me and my family, and I thank you
Great video thanks. All my express vans had this issue sooner or later and I always just lived with it. Your video gave me the most important info....where to even start looking for the problem! Turns out it wasn't my check valve, but I followed the three hoses with my fingers and eventually found a split/crushed section right where one attached to the manifold. I couldn't see what I was doing it was so far back behind everything, but there was enough room to get arms and hands back there and cut out the bad part and reattach it. Cold air flowing out of the vents is magical!!
Wow! Very nice!! Luckily the vacuum system isn't TOO complex on these vans, but the locations of the lines are the biggest hinderance. It's getting a little too hot outside to have the AC blowing at the windshield haha Glad it's working again! -Tim
Excellent information, I have had very poor heat in my 3500 savanna work van for two years now. Working in Ohio in the winter and not having heat when you come down off the rooftop is a BITCH. I replaced the lines and the check and watched the heat control valve that evidently was not getting enough vacuum to open it fully, now its fully functional. You Sir managed to keep a working man warm this coming winter...! Bravo !!!!
mine kicked the bucket in my work van and found this video and went and looked and that tube is fried! tomorrow is supposed to hit 100 so hopefully i can find some tubing to put on there. thanks!
Hooked it up and it didnt work, so i came back and rewatched the video... i forgot to hook the t part up lol...she works now! 3 bucks for the tubing bout an hour of time and some super greasy hands and arms i got a.c!! thanks again!
If the hoses were made of silicone rubber they would last a lot longer. It ticks me off that they are made of something that fails so quickly. Black rubber turns to charcoal inside a hot engine compartment. I am upgrading to silicone vac hoses. This video was very helpful because I didn't know about the check valve or where it was hidden.
Just long enough to last through the manufacturer's warranty! Seems to be the sad state of ALL industries these days. Hope the line upgrade went well! I know one of the lines goes up to the engine's intake plenum. Can't remember if it's accessible without taking off the engine cover inside the van.
@@VanwithTim The engine cover needs to come off to get the job done. Filthy hot work in a Texas summer. I could feel the hose leading to the engine. It was split open, so now I need to get up my ambition to remove the dog house. Meanwhile, I just drive with the window down.
@@normanwitzler9665 Ah man... Not a fun job, but you might be able to get it loose enough in under 10 minutes :) That is unless you want to remove the dog house from the van. Then there's the whole passenger seat removal process. Such a lovely design lol Stay cool!!
Got a $1400.00 estimate to get to the box to operate flow....watched this video....im 98% that your hose to the ball is the issue since I touched and broke the hose easily...satuday I will confirm. Thank you soooooo much ;) (You da man!)
I've been seeing so many comments saying the same thing this summer! In theory it should even help smooth out the engine idle having fixed a vacuum leak. Glad you have it figured out! Stay cool! -Tim
I decided to buy & use the [Dorman] Vacume Check-valve after seeing this video; That [Dorman] Vacume Check-valve is Good; shaking it you will hear a Ball unlike [AC Delco] Vacume Check-valve which is a Diaphram. When installed in a Verticle position; for the Ball to easily engage; Im assuming that a Ball inside can be more durable than a Material Based diaphram. Verticle means Reservoir-port at Bottom & Intake Manifold's-port above, the AC Controls-port positioned Horizontally; as directed towards the left. This eases engagement with Gravity assistance! Basically, You should install the [Dorman] Vacume Check-valve as the original is positioned as the manufacturers workers install it; not as another direction!
That's a great idea! My original valve was installed horizontally and I thought the Dorman check valve would work okay the same way. Maybe there wasn't enough airflow to move the ball into the "sealed" position when in a horizontal position. Using gravity to close the check ball is a perfect solution. Dorman should make a note of that on the packaging!
Unfortunately for us, we might not have [Dorman] brand & prices as an option; as Pep Boys is Closing down. In California, one of the last stores Manger said their being replaced by "Advanced Auto" and will not be a Retail-store distributor but 'Parts order' type of sales!
@@edmateos17 My first job was at a small mom and pop auto parts store. Seems I could find anything and everything no matter how odd in those dusty paper catalogs. I spent my college years at O'Reilly Auto. Was pleasantly surprised they had paper catalogs. (Although only the manager and myself knew how to use them). It's a fast changing world for sure.
On mine the line was disconnected to the vacuum reservoir so I thought for sure that would be the fix. After plugging it in, the A/C still doesn't work and the vehicle does not start. Any suggestions for next steps there? I'd assume other than unplugging that line...
I have the same vehicle. What would be the cause of little cold hair in idle stationary for long time, versus on the road its really cold. Also, over time in idle and stationary (waiting at parking lot), the flow of air at max diminishes while on and when I turn of the A/C unit after a while I turn it back on it starts to blow full speed at 4 (max). Its like if it freezes internally and little air passes through. Also, when the A/C is turned off driving down the highway, if you have it set to cold, you feel some cold air, if you set it to hot, you start getting warm air through the vents without even having the a/c on. Any ideas? These Chevy Express vans ALWAYS have A/C issues 😅 I also noticed that my MAX and regular cold vent settings are the only one that works like if the actuators not working properly. Do you have any videos on these?
Do you see any big voltage fluctuations when idling vs driving? It should show around 13.5-14.5 volts at idle and driving. If the alternator is bad, it could be dropping out at low RPMs and allowing the voltage to drop to 12.6v while running. You should also check the wiring harness above the blower motor under the hood. It will be a six wire connector like this: amzn.to/3RvnHPr Unfortunately, the pins in the connector are known for coming loose internally and causing a ton of electrical resistance (which causes a lot of heat and has even burned these vans to the ground). Definitely unplug the connector and look for any discoloration of the plug or terminals. It's also possible that your evaporator is freezing, especially if it has restricted airflow. If you remove the blower motor under the hood (three bolts - 30 second job) you can look inside to the left and ensure your evaporator is clean of debris. Spray it with a hose and make sure the water runs out through the drain on the bottom of the HVAC box. Here’s a video of the evaporator core access: th-cam.com/video/qY6pH7yRvzM/w-d-xo.html Also, if the system is off (knob on the far right set to “off”) you’ll still have air coming into the cabin while driving. This is because of the positive pressure in the front of the van, and the vacuum at the rear of the van (the air exits through a baffle behind the right rear tail light). The HVAC system is only closed off from the outside air when in MAX AC mode (recirculate mode). All other selections are fresh-air from outside.
@@VanwithTim Thanks very detailed explanations. Definitely subbed and hope others are reading this to sub too. I will check evaporator inside the air box. I noticed some leaves and stuff in there before through the harness opening. I actually replaced the blower motor harness that goes into the box. It was corroded as if water had gotten in there. The bottom resistor thingy on the blower motor harness on that amazon piece you posted was all rusted and one of the legs corroded completely on the resistor. Kind of odd it was rusted. The new one somewhat fixed the issue with the moisture coming through the vents, but the issue with mild cold air instead of really cold air when we are driving still persists. My dads mechanic is always checking the A/C Freon and tops it off if needed. I will clean the evaporator myself and check. Question, the van gets extremely hot under the hood (imagine the paint is falling off on the top side of the hood) and my dad did replace the radiator and the fan right behind the radiator. No other warnings or temperature fluctuations. You think the condenser could be clogged with bent fins causing the A/C issue while stationary. In my van, the transmission oil cooler is in the front, then the A/C condenser, then the radiator followed by the fan in the middle of the engine bay facing the serpentine belt. With regards to the right knob not switching between foot, to windshield, to face like if the actuator is stuck that diverts the vents, is that an issue with the color coded vacuum lines under the passenger foot-well or the actuator needs replacement?
@@CSJiGSaW08 Hmm that’s so strange! Sounds like most of the common troubleshooting items have been taken care of already. For the condenser, it wouldn’t hurt to spray it down with a hose to be sure it’s clean, but usually a dirty condenser or bent fins would affect the cooling at idle and not while driving. If it sounds like the blower motors airflow is audibly diminished while driving then returns when the van is stopped for a little bit, I would be looking at the vacuum system. You’re correct in that the color coded vacuum lines under the dash control the “mode” actuator (which directs the airflow: defrost, face, feet) The vacuum lines also control the “MAX AC” (aka - recirculate door actuator). The temperature actuator is fully electric though. It's rare (but not unheard of) to have any issue with the vacuum system inside the van unless it’s been physically damaged. I would certainly start with a check of the vacuum line running from the engine’s intake manifold to the check valve, then the check valve, then the vacuum accumulator ball below the battery tray, then the other line off of the check valve that leads through the firewall to the HVAC controls. Be careful, it’s common for the vacuum lines to crumble when you touch them. If they do crumble they were probably the issue to begin with and you can grab some generic vacuum line by the foot at the parts store. Note that the vacuum port on the intake manifold is kind of tough to reach from under the hood. You MIGHT need to remove the engine cover inside the van to gain better access. It does help to move the coolant overflow tank to the side when doing basically anything under the hood though. -Tim
@@VanwithTim thanks Tim will check on this and the vacuum lines. I remember long ago when everything worked fine, the compressor clutch would kick in with a clank noise every few minutes and would cycle and the A/C would blow very cold for long periods indefinitely. Now when I start the vehicle, the clutch kicks in with clank noise and never cycles that clank noise again. Does that sound familiar ? And be related to the cold air (little) while idle after about 15 minutes and get colder while driving down the freeway?
@@CSJiGSaW08 Certainly strange to hear anything other than a click from the clutch when the compressor turns on. It might be worth renting the AC gauge set from the parts store and seeing what your high and low side pressures look like. That would help point in the right direction. It would show if there were any internal restrictions in the system (a clogged orifice tube) or if the compressor is failing to build proper pressure. Here's a quick video on the gauges: th-cam.com/video/_Qt6UCmzRH4/w-d-xo.html And here's the chart he references for troubleshooting. You'll have to zoom in a bit to really read it, but that would 100% tell you if there's an issue with the AC system or the vacuum system. bit.ly/2UZkdGx Lots of other good videos on the AC "manifold" gauge set and how to draw conclusions from the readings!
My AC works fine but I do notice that after I passed 55 and I’m pushing on the gas it’s sputters like if it has like a vacuum leak or it’s not getting enough gas. Do you think this is the problem?
This fixed the top air vents in the rear but still no air from the front vents and still reads 80 to 90 from back vents even though psi is at 30, any way you can help me out? It’s an e-350 ford super duty van 2014
It’s been a while since I’ve had the van, but from the vacuum tee there were three connections: engine vacuum (connects to top of engine), vacuum reservoir under the battery tray, and the last went to the HVAC system. Sorry I don’t have more information!
Of the three ports on the Dorman check valve, it will NOT be the "tee" portion. That leaves the two parallel ports. With the "tee" port blocked with your thumb, you should only be able to suck air through one of the ports. That port will be the one to connect to the engine side of the vacuum line. The other port you weren't able to suck air through will connect to the vacuum ball under the battery tray. The "tee" port will be connected to the HVAC system. Note that my Dorman check valve allowed air to flow in both directions. It was bad out of the box. Had to order the OEM on Amazon.
So my van only blows hot but I can feel the compressor lines are ice cold and I also don’t get that hissing noise when I shut off my van. (It also only blows at feet and defrost. So change check valve first then of that doesn’t work move onto vacuum leaks?
Hey Joey - sounds like you have two separate issues here. The "mode" door is the one that's controlled by vacuum and changes the direction of the airflow. If it's not changing the airflow even when the van is running at idle, it sounds like there's a bigger issue than the check valve (don't worry, the system is pretty simple) Basically one vacuum line comes off of the engine, goes to the check valve, then from the check valve tees off to the vacuum reservoir and the HVAC controls. Many people have found the line between the engine and check valve crumbled or completely broken with age. Once replaced it should solve the mode door issue (and possibly smooth out any rough idle issues). **************** Temperature: The temperature blend door is actually 100% electrical. If working properly, it should make this noise: th-cam.com/video/tv55XtgJfUE/w-d-xo.html If not, check the fuses first and foremost. I can also send you an electrical diagram to help troubleshoot. It's pretty easy to get to if you need to replace it. Feel free to shoot me an email if you need that wiring diagram or fuse location, etc. VanWithTim@gmail.com Cheers! -Tim
Hope you can help me. I am replacing the valve along with the hoses. I had left the hoses attached to the valve so I would know where they go on the new one. When I went to get the parts the guy pulled the hoses off to measure them and I’m not sure which goes where. I have the AC/Delco replacement ordered and will be here tomorrow
Hey Michael, there are three ports on your new check valve. (Hopefully the AC Delco units are still black and white!) The black side is the vacuum source (top of engine manifold) The white side (directly across from the black side) goes down to the vacuum reservoir located under the battery. The “Tee” (90° from the other ports) goes to the inside of the van for your HVAC controls. Pause the video a little before and after the @1:18 mark and it should help with the general direction of two of the three lines.
Idle the van for about a minute then turn it off. Then listen closely to the climate control selector and change the "mode" (as seen @2:14) you should hear a small "hissssssssss" You might need to turn up your volume to hear mine. If yours doesn't make that noise, it's probably the check valve. To test the valve off of the vehicle, you can blow into the valve. Two ports will be free-flowing in either direction (suction / pressure) but one - the engine / vacuum feed connection - should only allow suction through and if you try blowing, it should block the air from flowing.
You can kind of see the rubber line going into the side of the upper intake manifold in this video: th-cam.com/video/_SPWo41Vfzk/w-d-xo.html Here's a still from the video with the location circled: drive.google.com/file/d/1uF1q_QMh7Fn__dDtZoEuRNy-HQ8nVsNW/ (This is on my 2005 6.0L engine but should be similar to the 5.3L and 4.8L)
@@VanwithTim I really appreciate u taking the time to show me that but are u saying I basicly need to drop the whole engine in order to get a new hose on there cuz I don't see any way of reaching back in there with the engine in the bay like it is and ofc my hose by the inlet port was burnt up and has holes so I needed to replace it but now I can't see where I took it out from to get it back on
@@VanwithTim at least I think it's the inlet hose that I need to reconnect when I ended up finding was both of the hoses on that little check valve you said to replace had holes on them and needed to be replaced I replace the hose to the vacuum canister with no problem but it's the other hose I can't get and the hose that goes to the electric controls is fine and still plugged in
@@VanwithTim also I'm in a 2014 model I don't think they are in the same spot because my hose was connected to the left side of the engine not the right side like in the vid you linked still really appreciate your help
@QuickShtick's Streaming Yeah that sounds like the engine intake vacuum hose. Don't think you'd be able to access it from under the hood without some REALLY long arms. The engine access cover is just four 10mm bolts and 4 latches though. Probably
Our 3500 has air normally only coming out of the defrost and floor. Once a day it will start blowing out of the vents the way its supposed to. Does the sound like the check valve or vacuum from the panel to the motor?
I would start with the check valve as it's the more common issue and also much easier to get to for testing. Also worth looking above the passenger footwell at the vacuum lines to make sure none are broken / disconnected.
Mine (3500) was doing the same thing until it finally stayed stuck that way, I also had very poor heat in the winter. Most of my problem was the main vacuum hose off the top of the engine that ran down to the check valve. It was crusty and burnt. 4 bucks for a new hose and a little sweat equity and I'm back in business. I also checked my vacuum with a gauge at the top of the engine were that tube connects just to make sure I had good vacuum. Reading was 18-20 inches of mercury which is great.
Hi. I have a 1997 Dodge Dakota with this problem. I cannot find a vacuum reservoir nor is it listed in my Haynes manual. I went to Dodge and they only list a Vacuum reservoir for the cruise control only. Is it possible for my truck to not have a Vacuum Reservoir for the blend doors? Thanks. PS. They no longer have any stock or idea of what check valve goes into my truck. Are they generic. How can I find the right one when I don't have a part number?
Sorry for the late reply - the 97 Dakota has both the recirculate / fresh air actuator and mode actuator (defrost, face, feet) controlled via engine vacuum. The temperature actuator is controlled via cable. The HVAC / cruise control vacuum check valve (they both utilize the same check valve simultaneously) is located right off of the brake booster check valve (connected to the brake booster check valve with a 90 degree elbow) Check valve part number on the 1997 Dakota is 4549209 amzn.to/3DVb2Q0 (no idea why it's so expensive or even if it's the cause of the issues on your truck) Feel free to email me if you'd like the blown up vacuum diagram! VanWithTim@gmail.com
@@VanwithTim thank you for the reply. I found the vacuum reservoir under the cowl on the passenger side. I doubt that's part of the problem as the cruise control works properly. I suspect something in the darkest recesses of the HVAC box under the dash or maybe the mode switch. The air blows well in Max AC mode even under load but in vent mode it looses air. It also gets worse as the truck heats up. Next I'll take it to a shop to get it smoked out.
Your vacuum line coming from the engine which connects to the check valve may be bad. Many are reporting that main vacuum feed line is crumbling due to age. You can check by disconnecting the check valve, starting the engine, and seeing if you feel vacuum on the line which goes to the engine. If you don’t, you need to replace the line.
Bro you are the only video out here speaks on this, I went under the hood and my line wasn't even connected to that vacuum ball. The air feels beautiful now thank you bro great video
did you have to take the battery out to connect to vacuum ball? i couldn't find the where the hoses are attached to the T but i did find one hose just dangling...when i put my finger over the opening of the hose it has suction...i think this is supposed to be connected to the vacuum ball under the battery?
Thanks very much for this video. I have a 3500 as a family car for my big family, and in Texas the AC is critically important. So I was vexed by the unusual aspect of temporary changes while driving and figured it was some sort of vacuum issue. Your video was very beneficial for me and my family, and I thank you
Appreciate the feedback and certainly glad it was an easy fix!
Best video about these van's hvac issues on TH-cam. Thanks.
I wear that I had a bad ground and this was causing exactly what you described. Smarter every day because your parents did a good job. Thanks!
You are a star! I had replaced the vacuum line, but missed the tee. It's fixed, and my wife is rejoicing.
Great video thanks. All my express vans had this issue sooner or later and I always just lived with it.
Your video gave me the most important info....where to even start looking for the problem!
Turns out it wasn't my check valve, but I followed the three hoses with my fingers and eventually found a split/crushed section right where one attached to the manifold.
I couldn't see what I was doing it was so far back behind everything, but there was enough room to get arms and hands back there and cut out the bad part and reattach it.
Cold air flowing out of the vents is magical!!
Wow! Very nice!!
Luckily the vacuum system isn't TOO complex on these vans, but the locations of the lines are the biggest hinderance.
It's getting a little too hot outside to have the AC blowing at the windshield haha
Glad it's working again!
-Tim
Thank you for the video. The hose on mine wasnt even plugged in. No idea what that was about but you helped me do a 3 minute $0 fix. ;)
Wow! Certainly the best type of fix!! 😅 very nice
I was looking for that loose line for 2 days
You video helped me locate the check valve thanks you
It's really tight under the hood in these vans. Glad the video helped!
Excellent information, I have had very poor heat in my 3500 savanna work van for two years now. Working in Ohio in the winter and not having heat when you come down off the rooftop is a BITCH. I replaced the lines and the check and watched the heat control valve that evidently was not getting enough vacuum to open it fully, now its fully functional. You Sir managed to keep a working man warm this coming winter...! Bravo !!!!
Oh man... Native Michigander here. Not sure how you made it that long without heat! Glad you're ready for the winter now buddy!
Cheers!
mine kicked the bucket in my work van and found this video and went and looked and that tube is fried! tomorrow is supposed to hit 100 so hopefully i can find some tubing to put on there. thanks!
These cheap plastic and rubber lines never seem to last. Or the second you touch it, they crumble to pieces.
Hope you get it fixed up soon!
Stay cool!
Hooked it up and it didnt work, so i came back and rewatched the video... i forgot to hook the t part up lol...she works now! 3 bucks for the tubing bout an hour of time and some super greasy hands and arms i got a.c!! thanks again!
@@CJ_412_ Glad it worked out! Certainly never fun getting shoulder deep on the engine bay blind haha.
Stay cool!
-Tim
Thank you for the video. Using this as a part of my study material for ASE A7.
very cool, I'll be on the lookout for a bad check valve or hoses disconnected/deteriorated
Was just glad it was an easy fix! (Well, second time around after replacing the defective Dorman brand check valve haha)
Cheers!
-Tim
Great how-to video! Thank you!!
If the hoses were made of silicone rubber they would last a lot longer. It ticks me off that they are made of something that fails so quickly. Black rubber turns to charcoal inside a hot engine compartment. I am upgrading to silicone vac hoses. This video was very helpful because I didn't know about the check valve or where it was hidden.
Just long enough to last through the manufacturer's warranty!
Seems to be the sad state of ALL industries these days.
Hope the line upgrade went well! I know one of the lines goes up to the engine's intake plenum. Can't remember if it's accessible without taking off the engine cover inside the van.
@@VanwithTim The engine cover needs to come off to get the job done. Filthy hot work in a Texas summer. I could feel the hose leading to the engine. It was split open, so now I need to get up my ambition to remove the dog house. Meanwhile, I just drive with the window down.
@@normanwitzler9665 Ah man...
Not a fun job, but you might be able to get it loose enough in under 10 minutes :)
That is unless you want to remove the dog house from the van. Then there's the whole passenger seat removal process. Such a lovely design lol
Stay cool!!
Good job only video found on this 💯
Incredible!! When I go up a hill, the vent always switch to defrost. Will this fix that issue? Thank you!!
Awesome video. Thanks brother this fixed my problem!
Got a $1400.00 estimate to get to the box to operate flow....watched this video....im 98% that your hose to the ball is the issue since I touched and broke the hose easily...satuday I will confirm. Thank you soooooo much ;) (You da man!)
I had the same issue and the vacuum lines crumbled in my hands. GM obviously used the lowest quality on the market.
I've been seeing so many comments saying the same thing this summer! In theory it should even help smooth out the engine idle having fixed a vacuum leak.
Glad you have it figured out!
Stay cool!
-Tim
I decided to buy & use the [Dorman] Vacume Check-valve after seeing this video;
That [Dorman] Vacume Check-valve is Good; shaking it you will hear a Ball unlike [AC Delco] Vacume Check-valve which is a Diaphram. When installed in a Verticle position; for the Ball to easily engage; Im assuming that a Ball inside can be more durable than a Material Based diaphram. Verticle means Reservoir-port at Bottom & Intake Manifold's-port above, the AC Controls-port positioned Horizontally; as directed towards the left. This eases engagement with Gravity assistance!
Basically, You should install the [Dorman] Vacume Check-valve as the original is positioned as the manufacturers workers install it; not as another direction!
That's a great idea! My original valve was installed horizontally and I thought the Dorman check valve would work okay the same way.
Maybe there wasn't enough airflow to move the ball into the "sealed" position when in a horizontal position.
Using gravity to close the check ball is a perfect solution.
Dorman should make a note of that on the packaging!
Unfortunately for us, we might not have [Dorman] brand & prices as an option; as Pep Boys is Closing down. In California, one of the last stores Manger said their being replaced by "Advanced Auto" and will not be a Retail-store distributor but 'Parts order' type of sales!
@@edmateos17 My first job was at a small mom and pop auto parts store.
Seems I could find anything and everything no matter how odd in those dusty paper catalogs.
I spent my college years at O'Reilly Auto. Was pleasantly surprised they had paper catalogs. (Although only the manager and myself knew how to use them).
It's a fast changing world for sure.
On mine the line was disconnected to the vacuum reservoir so I thought for sure that would be the fix. After plugging it in, the A/C still doesn't work and the vehicle does not start. Any suggestions for next steps there? I'd assume other than unplugging that line...
Thank you I think this is going on with my van.when the ac is on it blows out of vents,defrost,and foot vents.
Sounds like it's definitely something in the vacuum system.
A lot of people have also found their vacuum lines under the hood in need of replacement.
Thanks!
I have the same vehicle. What would be the cause of little cold hair in idle stationary for long time, versus on the road its really cold. Also, over time in idle and stationary (waiting at parking lot), the flow of air at max diminishes while on and when I turn of the A/C unit after a while I turn it back on it starts to blow full speed at 4 (max). Its like if it freezes internally and little air passes through. Also, when the A/C is turned off driving down the highway, if you have it set to cold, you feel some cold air, if you set it to hot, you start getting warm air through the vents without even having the a/c on. Any ideas? These Chevy Express vans ALWAYS have A/C issues 😅 I also noticed that my MAX and regular cold vent settings are the only one that works like if the actuators not working properly. Do you have any videos on these?
Do you see any big voltage fluctuations when idling vs driving? It should show around 13.5-14.5 volts at idle and driving. If the alternator is bad, it could be dropping out at low RPMs and allowing the voltage to drop to 12.6v while running.
You should also check the wiring harness above the blower motor under the hood. It will be a six wire connector like this: amzn.to/3RvnHPr
Unfortunately, the pins in the connector are known for coming loose internally and causing a ton of electrical resistance (which causes a lot of heat and has even burned these vans to the ground).
Definitely unplug the connector and look for any discoloration of the plug or terminals.
It's also possible that your evaporator is freezing, especially if it has restricted airflow.
If you remove the blower motor under the hood (three bolts - 30 second job) you can look inside to the left and ensure your evaporator is clean of debris. Spray it with a hose and make sure the water runs out through the drain on the bottom of the HVAC box. Here’s a video of the evaporator core access: th-cam.com/video/qY6pH7yRvzM/w-d-xo.html
Also, if the system is off (knob on the far right set to “off”) you’ll still have air coming into the cabin while driving. This is because of the positive pressure in the front of the van, and the vacuum at the rear of the van (the air exits through a baffle behind the right rear tail light). The HVAC system is only closed off from the outside air when in MAX AC mode (recirculate mode). All other selections are fresh-air from outside.
@@VanwithTim Thanks very detailed explanations. Definitely subbed and hope others are reading this to sub too.
I will check evaporator inside the air box. I noticed some leaves and stuff in there before through the harness opening. I actually replaced the blower motor harness that goes into the box. It was corroded as if water had gotten in there. The bottom resistor thingy on the blower motor harness on that amazon piece you posted was all rusted and one of the legs corroded completely on the resistor. Kind of odd it was rusted. The new one somewhat fixed the issue with the moisture coming through the vents, but the issue with mild cold air instead of really cold air when we are driving still persists. My dads mechanic is always checking the A/C Freon and tops it off if needed. I will clean the evaporator myself and check.
Question, the van gets extremely hot under the hood (imagine the paint is falling off on the top side of the hood) and my dad did replace the radiator and the fan right behind the radiator. No other warnings or temperature fluctuations. You think the condenser could be clogged with bent fins causing the A/C issue while stationary. In my van, the transmission oil cooler is in the front, then the A/C condenser, then the radiator followed by the fan in the middle of the engine bay facing the serpentine belt.
With regards to the right knob not switching between foot, to windshield, to face like if the actuator is stuck that diverts the vents, is that an issue with the color coded vacuum lines under the passenger foot-well or the actuator needs replacement?
@@CSJiGSaW08 Hmm that’s so strange! Sounds like most of the common troubleshooting items have been taken care of already. For the condenser, it wouldn’t hurt to spray it down with a hose to be sure it’s clean, but usually a dirty condenser or bent fins would affect the cooling at idle and not while driving.
If it sounds like the blower motors airflow is audibly diminished while driving then returns when the van is stopped for a little bit, I would be looking at the vacuum system.
You’re correct in that the color coded vacuum lines under the dash control the “mode” actuator (which directs the airflow: defrost, face, feet)
The vacuum lines also control the “MAX AC” (aka - recirculate door actuator).
The temperature actuator is fully electric though.
It's rare (but not unheard of) to have any issue with the vacuum system inside the van unless it’s been physically damaged.
I would certainly start with a check of the vacuum line running from the engine’s intake manifold to the check valve, then the check valve, then the vacuum accumulator ball below the battery tray, then the other line off of the check valve that leads through the firewall to the HVAC controls.
Be careful, it’s common for the vacuum lines to crumble when you touch them. If they do crumble they were probably the issue to begin with and you can grab some generic vacuum line by the foot at the parts store.
Note that the vacuum port on the intake manifold is kind of tough to reach from under the hood. You MIGHT need to remove the engine cover inside the van to gain better access. It does help to move the coolant overflow tank to the side when doing basically anything under the hood though.
-Tim
@@VanwithTim thanks Tim will check on this and the vacuum lines. I remember long ago when everything worked fine, the compressor clutch would kick in with a clank noise every few minutes and would cycle and the A/C would blow very cold for long periods indefinitely. Now when I start the vehicle, the clutch kicks in with clank noise and never cycles that clank noise again. Does that sound familiar ? And be related to the cold air (little) while idle after about 15 minutes and get colder while driving down the freeway?
@@CSJiGSaW08 Certainly strange to hear anything other than a click from the clutch when the compressor turns on.
It might be worth renting the AC gauge set from the parts store and seeing what your high and low side pressures look like. That would help point in the right direction.
It would show if there were any internal restrictions in the system (a clogged orifice tube) or if the compressor is failing to build proper pressure.
Here's a quick video on the gauges: th-cam.com/video/_Qt6UCmzRH4/w-d-xo.html
And here's the chart he references for troubleshooting. You'll have to zoom in a bit to really read it, but that would 100% tell you if there's an issue with the AC system or the vacuum system. bit.ly/2UZkdGx
Lots of other good videos on the AC "manifold" gauge set and how to draw conclusions from the readings!
My AC works fine but I do notice that after I passed 55 and I’m pushing on the gas it’s sputters like if it has like a vacuum leak or it’s not getting enough gas. Do you think this is the problem?
Mine works fine and when I pass 55 it stops coming out the vents and comes out of the defrost and floor barely...
Thanks for the info. Can you tell me where the line connects from the T connector to the engine. Mines is missing 😢😢
This fixed the top air vents in the rear but still no air from the front vents and still reads 80 to 90 from back vents even though psi is at 30, any way you can help me out? It’s an e-350 ford super duty van 2014
What if I have 2 hvac control coming out. Where does the other one goes to?
Thanks, 👍🏼
I have a similar issue with my van and the rear ac is no longer working, would this be related to this?
Which direction does the check valve install?
How did you replace it with the motor in the way?
Where does the small hard live connect to?
It’s been a while since I’ve had the van, but from the vacuum tee there were three connections: engine vacuum (connects to top of engine), vacuum reservoir under the battery tray, and the last went to the HVAC system.
Sorry I don’t have more information!
Dorman check valve " pt #47170" flow direction is not labeled. Please advise. TYI
Of the three ports on the Dorman check valve, it will NOT be the "tee" portion.
That leaves the two parallel ports. With the "tee" port blocked with your thumb, you should only be able to suck air through one of the ports. That port will be the one to connect to the engine side of the vacuum line. The other port you weren't able to suck air through will connect to the vacuum ball under the battery tray. The "tee" port will be connected to the HVAC system. Note that my Dorman check valve allowed air to flow in both directions. It was bad out of the box. Had to order the OEM on Amazon.
So my van only blows hot but I can feel the compressor lines are ice cold and I also don’t get that hissing noise when I shut off my van. (It also only blows at feet and defrost. So change check valve first then of that doesn’t work move onto vacuum leaks?
Hey Joey - sounds like you have two separate issues here. The "mode" door is the one that's controlled by vacuum and changes the direction of the airflow.
If it's not changing the airflow even when the van is running at idle, it sounds like there's a bigger issue than the check valve (don't worry, the system is pretty simple)
Basically one vacuum line comes off of the engine, goes to the check valve, then from the check valve tees off to the vacuum reservoir and the HVAC controls.
Many people have found the line between the engine and check valve crumbled or completely broken with age. Once replaced it should solve the mode door issue (and possibly smooth out any rough idle issues).
****************
Temperature:
The temperature blend door is actually 100% electrical. If working properly, it should make this noise: th-cam.com/video/tv55XtgJfUE/w-d-xo.html
If not, check the fuses first and foremost.
I can also send you an electrical diagram to help troubleshoot. It's pretty easy to get to if you need to replace it.
Feel free to shoot me an email if you need that wiring diagram or fuse location, etc.
VanWithTim@gmail.com
Cheers!
-Tim
Hope you can help me. I am replacing the valve along with the hoses. I had left the hoses attached to the valve so I would know where they go on the new one. When I went to get the parts the guy pulled the hoses off to measure them and I’m not sure which goes where.
I have the AC/Delco replacement ordered and will be here tomorrow
Hey Michael, there are three ports on your new check valve. (Hopefully the AC Delco units are still black and white!)
The black side is the vacuum source (top of engine manifold)
The white side (directly across from the black side) goes down to the vacuum reservoir located under the battery.
The “Tee” (90° from the other ports) goes to the inside of the van for your HVAC controls.
Pause the video a little before and after the @1:18 mark and it should help with the general direction of two of the three lines.
@@VanwithTim wow! Thanks for the quick reply! Very helpful.
@@michaelclover9186 Sure thing. Let me know if you need any further assistance tomorrow! Good luck!
@@VanwithTim Installed and working correctly!!!! Thanks again!!
Wow. Great video and great info on The Best All-Around Vehicle Ever Built-- The Expresavana
Yes. But how do you check the check valve itself? Thks..jc
Idle the van for about a minute then turn it off. Then listen closely to the climate control selector and change the "mode" (as seen @2:14) you should hear a small "hissssssssss"
You might need to turn up your volume to hear mine.
If yours doesn't make that noise, it's probably the check valve.
To test the valve off of the vehicle, you can blow into the valve. Two ports will be free-flowing in either direction (suction / pressure) but one - the engine / vacuum feed connection - should only allow suction through and if you try blowing, it should block the air from flowing.
Can you show where the inlet is on the actual engine I can't find it for the life of me
You can kind of see the rubber line going into the side of the upper intake manifold in this video: th-cam.com/video/_SPWo41Vfzk/w-d-xo.html
Here's a still from the video with the location circled: drive.google.com/file/d/1uF1q_QMh7Fn__dDtZoEuRNy-HQ8nVsNW/
(This is on my 2005 6.0L engine but should be similar to the 5.3L and 4.8L)
@@VanwithTim I really appreciate u taking the time to show me that but are u saying I basicly need to drop the whole engine in order to get a new hose on there cuz I don't see any way of reaching back in there with the engine in the bay like it is and ofc my hose by the inlet port was burnt up and has holes so I needed to replace it but now I can't see where I took it out from to get it back on
@@VanwithTim at least I think it's the inlet hose that I need to reconnect when I ended up finding was both of the hoses on that little check valve you said to replace had holes on them and needed to be replaced I replace the hose to the vacuum canister with no problem but it's the other hose I can't get and the hose that goes to the electric controls is fine and still plugged in
@@VanwithTim also I'm in a 2014 model I don't think they are in the same spot because my hose was connected to the left side of the engine not the right side like in the vid you linked still really appreciate your help
@QuickShtick's Streaming Yeah that sounds like the engine intake vacuum hose.
Don't think you'd be able to access it from under the hood without some REALLY long arms.
The engine access cover is just four 10mm bolts and 4 latches though. Probably
Our 3500 has air normally only coming out of the defrost and floor. Once a day it will start blowing out of the vents the way its supposed to. Does the sound like the check valve or vacuum from the panel to the motor?
I would start with the check valve as it's the more common issue and also much easier to get to for testing.
Also worth looking above the passenger footwell at the vacuum lines to make sure none are broken / disconnected.
Mine (3500) was doing the same thing until it finally stayed stuck that way, I also had very poor heat in the winter. Most of my problem was the main vacuum hose off the top of the engine that ran down to the check valve. It was crusty and burnt. 4 bucks for a new hose and a little sweat equity and I'm back in business. I also checked my vacuum with a gauge at the top of the engine were that tube connects just to make sure I had good vacuum. Reading was 18-20 inches of mercury which is great.
Hi. I have a 1997 Dodge Dakota with this problem. I cannot find a vacuum reservoir nor is it listed in my Haynes manual. I went to Dodge and they only list a Vacuum reservoir for the cruise control only. Is it possible for my truck to not have a Vacuum Reservoir for the blend doors? Thanks. PS. They no longer have any stock or idea of what check valve goes into my truck. Are they generic. How can I find the right one when I don't have a part number?
Sorry for the late reply - the 97 Dakota has both the recirculate / fresh air actuator and mode actuator (defrost, face, feet) controlled via engine vacuum. The temperature actuator is controlled via cable.
The HVAC / cruise control vacuum check valve (they both utilize the same check valve simultaneously) is located right off of the brake booster check valve (connected to the brake booster check valve with a 90 degree elbow)
Check valve part number on the 1997 Dakota is 4549209 amzn.to/3DVb2Q0 (no idea why it's so expensive or even if it's the cause of the issues on your truck)
Feel free to email me if you'd like the blown up vacuum diagram!
VanWithTim@gmail.com
@@VanwithTim thank you for the reply. I found the vacuum reservoir under the cowl on the passenger side. I doubt that's part of the problem as the cruise control works properly. I suspect something in the darkest recesses of the HVAC box under the dash or maybe the mode switch. The air blows well in Max AC mode even under load but in vent mode it looses air. It also gets worse as the truck heats up. Next I'll take it to a shop to get it smoked out.
@@1lfp903 Wow that's an odd ball! Hope it's figured out without too much financial pain. Best of luck with it!
what head unit is that
Mine still doing the same thing after replacing that valve
Your vacuum line coming from the engine which connects to the check valve may be bad. Many are reporting that main vacuum feed line is crumbling due to age. You can check by disconnecting the check valve, starting the engine, and seeing if you feel vacuum on the line which goes to the engine. If you don’t, you need to replace the line.
@@VanwithTim i already replaced it and still doing the same. I’m gonna have the ac Freon checked up to swig its low