Hey! Check out the description if you have this problem. I put a lot of info in there! Tools: A/C Gauges: amzn.to/3LyCdET Vacuum Pump: amzn.to/3ENW7be Schrader Valve Quick Removal Tool: amzn.to/3PJ4afL Supplies: R134a Refrigerant: amzn.to/461nnyX Low Pressure Valves: amzn.to/3RztdmP High Pressure Valve: amzn.to/3PqChYw UV Dye: amzn.to/48AvJzs HVAC O-Ring Kit: amzn.to/3rnURIQ As an Amazon Associate I earn from qualifying purchases.
So glad I found this video!!! 1999 GMC Sierra 1500 Single cab SWB 2WD. 4.8L. Replaced both Schrader valves. Recharged and 😮 cold air again. Shop quoted my dad 1200 to fix it. 😡 I fixed in 20 minutes with this video thanks
@@BigBlockSeasonhe said he drew a 30-45 minute vacuum. It should have been mentioned that if a system is opened in humid ambient conditions, and for any length of time, it's open, the accumulator likely will absorb moisture in its dessicant. You will find that shops follow that mfr. recommendation and the parts and labor goes up when run through their business and their books or parts department. They comply with EPA regulations and spend a lot so they charge consumers.
2001 Silverado bought new by my papaw. Ice cold air. Few year back it was not blowing cold and was just barely blowing at all. That's wierd? Took a bit to figure out cause it was my Papaws truck and he's been gone now 12+yrs. Thinking about it I asked "what was I missing?" Turns out it was the clogged in cab airfilter. Had about an 1 inch or dust, dirt, tree detritus, etc😂 replaced filter and cold air flowed once again.😊 I think he was "guiding my hands" so to speak. 😊 I miss him.❤
He'd be proud you got it fixed. Just imagine all the places he went to get all that dust and dirt in the air filter. That truck must have had some awesome adventures! I love this story 👍
Dude thank you! It's been 100 degrees or so for like a month where I'm at and my DD Tahoe has not been letting the compressor kick on to charge the system. This was an eye-opening video since I don't know much about AC systems.
Yes great video. I had an obvious bad high side valve leak . Amazon had a shrader valve upgrade so I figured that’s better than a little plastic ball. Mine had been repaired again in o9 so apparently they go bad fairly often!!!
I believe “Mastercool (81490 R134A Valve Core Remover Installer, Yellow Gold, 6.8 inch” is the tool you are talking about that allows you to change the schrader valve without draining the system. I had an 2001 Silverado and the AC wasn’t blowing as cold as it should. When I added Freon, the schrader valve started leaking. I was able to use the above tool to get it changed out. It was a little tricky. I had to put some grease on top of the schrader valve to get it to stick to the tool. I hope this helps someone out.
@@kylelaw7210 I used this exact too for my 03 Sierra. Had the same experience with the valve not wanting to stay in the tool correctly, but I found that you can VERY SLIGHTLY crimp the part the holds it.
Let me tell ya my friend ...You have the Best GMT800 videos on all of RUclips. Just picked up a 2001 suburban 1500 5.3 VORTEC .😁 with 170,000 miles on her. What a beast of a truck. Engine runs like a sewing machine. Keep up the Awesome videos. 🤠
I had the exact same problem with the low side shrader valve and zero freon , replaced it , pulled vacuum it held and added the correct freon by weight and she cools like brand new , didn't do the dye as it was a rush job , Summer on the Texas Gulf Coast !
My 95 Sonoma leaks down about every 6-8 months. I checked the two obvious Schrader valves and they weren't leaking. I was unaware there was a Schrader valve behind the pressure switch. Also, thanks for linking to the other equipment used. I can not seem to find a new valve cap that actually fits on the low pressure side tho.
The schrader valve behind the low pressure switch doesn't do anything while the switch is on the accumulator. One of the more common leaks on GM is the seam where the compressor is put together. The dye will help identify that.
All my relays and fuses are good I’m gonna bypass the safety switch to see if my ac comp kicks on and if so I’m going to check all the leak prone valves you described and proceed with your repair
Owned an 03 Suburban for 6 years used. Plastic coolant fittings, AC, blend door actuators, gauge cluster, radio, climate control, window regulators, cheap plastic door panels, door lock actuators, inoperable window washer system and peeling headliners are all major problems I had to deal with. Switched to Ford lol.
Just replace the schrader valve on that fill nipple every time you go to fill/refill the freon. @:47 It gets hot (I guess). It breaks just touching it. I learned all of this great info when a mechanic wanted to charge me $600+ (5 years ago) for a line replacement. I fixed it with a .10cent per dozen schrader valve, and vac, Harbor Freight harness and 4-5 cans of refrigerant all for less than $100. Now when I refill, It costs about $20. just for the cans. Chevy Suburban 2500 - 2001 Vortec 8.1ltr (496ci). My new problem I discovered today is that the blower fan was running with the ignition turned off and ran my battery down. It's some sort of control module under the glove box that has to be replaced and you can turn the blower fan off by pulling out a 30amp fuse that goes to the front AC. I haven't looked up the part yet. I'm expecting my actuators to start going any day now, so I may need to go to the auto salvage yard to part hunt. Thanks for the video!
I wasn't sure what the problem was on my 2002. So I just replaced everything in the AC system. Everything down to the lines lol works beautifully. But stay away from UAC parts, particularly their lines!!!! I was trying and trying to get one of the lines to seal and eventually discovered that the fitting on the end was machined too short! It never would have sealed. Replaced it with Four Seasons line and it was right as rain. In fact, I think my entire AC system is Four Seasons (except condenser, that is a Denso).
Thanks Matt! This gives me a little hope on my father in laws 1998 Chevy Silverado 4x4 2500.... Someone told him that the pump is bad, but I'll go check for that pressure valve. The pump is definitely not coming on and fuse is good. Thanks for the great video! Well documented and discriptive! Also communicated well! Thumbs up AND Subscribed!
Great video. My 05 suburban intermittently does not have AC, and after some troubleshooting I believe it is either the high pressure switch, or the compressor itself.
@@twiztid6977420 Yea that is an idea. I was going to try jumping it with a paper clip. The high pressure switch is located behind the A/C compressor on this model so it is a bit of a pain to get to. Have to jack the car up to get behind the compressor.
@@twiztid6977420 Yea lol. The low pressure switch I did the paper clip test on and it didn't make a difference. The A/C does work like 90% of the time so I haven't been super motivated to get after it. Plus up here in northern New England summer is already over
My favorite is reaching up under the passenger side dash to replace the actuator. It's 5 minute job that takes over an hour and then you feel it for the next three days.
Hey some great tips; My 99 C/3500 5.7 dually dump truck will be going into a local shop tomorrow to find out were it is leaking, I did buy 1 Schrader valve for it; So I guess I should have replaced all off them, But I'll find out tomorrow where it's leaking tomorrow, But this will aid me me in the conversation. Thanks again for the very useful info. & video as well.
@@MattsShop Well it turned out to be the shops equipment was the cause for a false reading, & the mechanic had to spend over $ 600.00 for new lines, & gauges with some other items he let me watch him do the leak test then showed me how it as not loosing pressure it took almost 2 cans of refrigerant, But the system is working like new again. Watching your video was very helpful as he did the whole procedure the same way you did. So I felt very comfortable watching him go thru the procedure, & the A/C system did not require anything new other than a charge. Thanks again for your video.
Gotta check the front HVAC fuse in the engine bay as it’s common to blow. If blower setting 5 stops working but all other settings work but the air could blow a little better, before changing the blower and resistor, check the fuse. Should be a small 30amp near the left rear parking lamp fuse. If you have a problem like mine, that fuse was SUPER blown. Changed it and boom bam we’re back in action.
Have you a video on the doors acting up. I put in a new climate control panel. 2004 6.0L 2500HD. This video was the same fix on my AC i have split climate control, heat / AC for left- right. Some or one of the actuator doors isn't behaving with the control panel
I have a 2003 GMC 2500 HD the blower motor will not turn off I went through the new resistor 40 amp fuse 30 amp fuse and control module on - still have blower going on with key off? Which way do I go? Hello
I have an 06. My ac does the blinking snow flake when it rains or I go through the car wash. Whatever gets wet will dry and it comes back on. I’ve changed the fresh air sensor in front of the radiator but it still does it. Any ideas?
A) High side valve... You need to use blue lock tight... When I unscrewed cap to check it. It unscrewed. B) Compressor not come on to fill ? Connect the 2 wires on low side. Compressor still not coming on with 2 wires on low ; then connect high side switch wire wire to positive batt
I had an issue with mine when I got my truck my friend fixes cars and replaced what used to be did now the same issue is their such thing u can put too much refrigeration with stop leak too clog the strainer again?
Well...I have 3 of these trucks, since new The one with the least miles...has 290k. They all still work fine. Perhaps regular maintenance comes into play?
You know what really sucks? Even the new replacement valves and fittings leak after a year !!! Manufacturers are building nothing but JUNK!!!! I had a 2000 GMC Sierra, I replaced those parts in 2011, prior to that the A/C had been working great, nice and cold. Every other year after that I had to replace them! I gave the truck to my son, earlier in 2024. It still runs good, and the A/C works fine..........until next year..........
I have a 2000 silverado with the 5.3. My AC blows ice cold, but my compressor stays on 24/7. After about 30 minutes of driving, the ac "freezes up" I thought it was strange as well that when I turn on the circulation button on the climate control it automatically kicks on the compressor, even when I don't have the AC button lit up. Any ideas on this issue?
@matts shop what would cause a 03 tahoe 5.3 to blow freezing cold while driving come to a stop and imediatly warm air ? Any help would be appreciated never been able to figure it out of all the years i have owned it
Everybody keeps having this problem. I am not exactly sure. A lot of people have suggested the A/C compressor is BAD. It runs well when the engine is at higher RPM then at a stop the RPM drop and the compressor can't move enough refrigerant. The test would be to test the high side pressure port of the system to see if the compressor is producing high enough pressures at idle.
Ok with no air coming out of the vents I checked all the fuses that are for the ac and they were all good I replaced them anyways . So then I replaced the blower motor and still had no air . So I replaced the resistor and the blower . I was sure that would fix the problem and no . I assumed ok maybe it would be the controls that control the air and I tried it on 3 different controls and nothing . What else would you recommend me to try I really don’t know what else to do
Great video, brother! My 2001 Silverado AC clutch will only engage when I jump the relay 87 to 30. I tried a relay that works and the clutch would not engage. It only engages when I jump it. The fuses are good too. The refrigerant is good. What do you think my issue may be, please? Thank you!
Hi Matt I just came across ur video. I have a 2004 Chevy Tahoe about a year ago I took it to amco they charged me $1200 to "FIX" my a/c but about a month later the front ac stoped blowing it blows a little bit like when im on the freeway. then it stops. i changed the blower motor. still the same. Only the the back ac works. any helpful tips i should try.
Hey Matt, any experience with blower motor issues? I had ice cold air. I went through a car wash and it stopped working. A compressor comes on and rear AC is cold and works fine. I have changed the blower motor and resistor - actually ive tried two of each. The blower motor simply does not come on. Simple as that. I have checked fuses and I had a mechanic friend check fuses, etc.
I didn't lol. I just keep it on a battery charger. You can get a modern alternator off a Datsun truck that doesn't need that complicated charging system. I still need to do it.
cool it you have the alt and reg still mounted in place be great to see the cannon plug connection from the reg to the harness, I bought new both of them. Just want to connect it. awesome to know a Datson will mount without making a new mounting device @@MattsShop
I jump the switch first. 99% of the time it has leaked too low for the switch to turn on the compressor. If jumping at the switch doesn't work there is some other electrical problem.
is there a temp the air from the vents should be reaching? I just got my A/C repaired and when its really hot like high 90s outside, my '03 Tahoe only gets down to about 70 degrees coming out of the vents while idle. I have thermometer on the vent. We have taken i back multiple times but still the same issue. Any ideas?
Now when I get up to freeway speeds, it gets pretty damn cold and it’s fine. It’s just an issue when I’m idling. The fan clutch is good, but I’m thinking of changing it anyway because if I lean on the RPMs for a long time, it will cool down.
What an awesome video showcasing a well known problem and it's fix. I'm an 07' Avalanche guy with no A/C & working compressor. Thanks for the awesome tutorial. Sub'd! BTW, on my 07 Avalanche, I was always under the impression that it is a huge design flaw that they failed to include a serviceable cabin filter for the HVAC system, but I saw you making mention to one! Does it exist? 🤯 Can you include the PN#s?
Thank you! Thanks for the sub. It is a very annoying problem! They removed the cabin air filters in 2003. This 2001 Chevy Silverado has cabin air filters your 2007 Avalanche doesn't. They took them out!
yup. my '02 avalanche had the schrader valve replaced. a year later the evaporator coil blew. Maybe the leak is protecting the evaporator coil. Maybe it was engineered that way!
It will still leak out in 2 days. I just tried that and it failed. Maybe a custom metal lid with Teflon tape would hole, but I prefer to fix the underlying problem.
They have a small tube in the middle that makes it go from high pressure to low pressure. It's called the orifice tube. It's inside the tube with the nut on it between the ports.
As soon as you take one of those little vows out moisture gets into the system moisture is the worst thing for AC has to get evaporated evap to get all the moisture out 👀
I don't know but I love driving by 2014 and newer Chevy trucks and they have all their windows down guys pouring sweat and it's 90 plus degrees out because his condenser broke. I love it! Meanwhile, he's making that huge payment for what to sweat balls or do upper control arms every 20,000 and transmissions every 75-100k ye I'll pass
It's maddening that they don't make that port replaceable like the high side. And it's double maddening that you have to replace the whole upper refrigerant line (not just the section with the low pressure port) to fix the bad port (not just bad Shrader valve).
Why would you need to replace the low side one? It’s welded because the shrader valve is serviceable. The high side one is not serviceable from the factory. Throw it out and replace it with a Dorman that also uses a serviceable shrader valve.
My 2000 Express a/c stopped working. Clutch cycles on and off every few seconds. Jumped low pressure switch and compressor comes on. Seems like freon isn't going from can into system and gauge isn't moving. Suggestions?
@@RailFan61 before doing away with the compressor make sure you are using the Freon tap correctly! Don’t screw it down thinking “I poked a hole in it” then unscrew it all the way because then it won’t work.
Hey! Check out the description if you have this problem. I put a lot of info in there!
Tools:
A/C Gauges: amzn.to/3LyCdET
Vacuum Pump: amzn.to/3ENW7be
Schrader Valve Quick Removal Tool: amzn.to/3PJ4afL
Supplies:
R134a Refrigerant: amzn.to/461nnyX
Low Pressure Valves: amzn.to/3RztdmP
High Pressure Valve: amzn.to/3PqChYw
UV Dye: amzn.to/48AvJzs
HVAC O-Ring Kit: amzn.to/3rnURIQ
As an Amazon Associate I earn from qualifying purchases.
So glad I found this video!!! 1999 GMC Sierra 1500 Single cab SWB 2WD. 4.8L. Replaced both Schrader valves. Recharged and 😮 cold air again. Shop quoted my dad 1200 to fix it. 😡 I fixed in 20 minutes with this video thanks
You're welcome! That's a crazy price and they always leak bad.
@@MattsShop can you do a video on leak detection for the whole system. ?
Did you use a vacuum pump to get all the moisture out of the system?
@@BigBlockSeasonhe said he drew a 30-45 minute vacuum.
It should have been mentioned that if a system is opened in humid ambient conditions, and for any length of time, it's open, the accumulator likely will absorb moisture in its dessicant.
You will find that shops follow that mfr. recommendation and the parts and labor goes up when run through their business and their books or parts department.
They comply with EPA regulations and spend a lot so they charge consumers.
Replace the high side with a dorman 800-955. This replaces the old style with a schrader valve.
Yea, it's wayy better. You can swap the valve out with that special tool without having to drain it.
THANKS TO YOUR VIDEO, I'll be fixing my '02 Chevrolet 1500 Suburban 5.3L Z71 AC this week as soon as I get the parts and tools!
2001 Silverado bought new by my papaw. Ice cold air. Few year back it was not blowing cold and was just barely blowing at all. That's wierd? Took a bit to figure out cause it was my Papaws truck and he's been gone now 12+yrs. Thinking about it I asked "what was I missing?" Turns out it was the clogged in cab airfilter. Had about an 1 inch or dust, dirt, tree detritus, etc😂 replaced filter and cold air flowed once again.😊 I think he was "guiding my hands" so to speak. 😊 I miss him.❤
He'd be proud you got it fixed. Just imagine all the places he went to get all that dust and dirt in the air filter. That truck must have had some awesome adventures! I love this story 👍
Dude thank you! It's been 100 degrees or so for like a month where I'm at and my DD Tahoe has not been letting the compressor kick on to charge the system. This was an eye-opening video since I don't know much about AC systems.
Yes great video. I had an obvious bad high side valve leak . Amazon had a shrader valve upgrade so I figured that’s better than a little plastic ball. Mine had been repaired again in o9 so apparently they go bad fairly often!!!
I believe “Mastercool (81490 R134A Valve Core Remover Installer, Yellow Gold, 6.8 inch” is the tool you are talking about that allows you to change the schrader valve without draining the system. I had an 2001 Silverado and the AC wasn’t blowing as cold as it should. When I added Freon, the schrader valve started leaking. I was able to use the above tool to get it changed out. It was a little tricky. I had to put some grease on top of the schrader valve to get it to stick to the tool. I hope this helps someone out.
Yes, that is the tool I'm talking about. It helps a lot if your refrigerant hasn't already drained down.
@@MattsShop I didn’t have gauges or a vacuum pump so it saved me a ton.
@@kylelaw7210 I used this exact too for my 03 Sierra. Had the same experience with the valve not wanting to stay in the tool correctly, but I found that you can VERY SLIGHTLY crimp the part the holds it.
Let me tell ya my friend ...You have the Best GMT800 videos on all of RUclips. Just picked up a 2001 suburban 1500 5.3 VORTEC .😁 with 170,000 miles on her. What a beast of a truck. Engine runs like a sewing machine. Keep up the Awesome videos. 🤠
Thanks really I appreciate it. I have plenty more tips coming. That's a great year! Keep her runnin.
That 5.3 v8 is the best engine I've ever owned.
High side fittings leaks are more common than low side, but this is the case with every GM R-134 systems, among others.
I had the exact same problem with the low side shrader valve and zero freon , replaced it , pulled vacuum it held and added the correct freon by weight and she cools like brand new , didn't do the dye as it was a rush job , Summer on the Texas Gulf Coast !
You did a perfect job! Now your truck's runnin nice and cool.
You are the king of GMT800 video! I have learned so much.
Thanks! I have a lot more to teach!
My 95 Sonoma leaks down about every 6-8 months. I checked the two obvious Schrader valves and they weren't leaking. I was unaware there was a Schrader valve behind the pressure switch. Also, thanks for linking to the other equipment used. I can not seem to find a new valve cap that actually fits on the low pressure side tho.
The schrader valve behind the low pressure switch doesn't do anything while the switch is on the accumulator. One of the more common leaks on GM is the seam where the compressor is put together. The dye will help identify that.
All my relays and fuses are good I’m gonna bypass the safety switch to see if my ac comp kicks on and if so I’m going to check all the leak prone valves you described and proceed with your repair
Owned an 03 Suburban for 6 years used. Plastic coolant fittings, AC, blend door actuators, gauge cluster, radio, climate control, window regulators, cheap plastic door panels, door lock actuators, inoperable window washer system and peeling headliners are all major problems I had to deal with. Switched to Ford lol.
Have an '06 Silverado 1500 with the 5.3. Never had a problem in 146,000 miles. A.C. is still as cold as when new.
You're lucky. You got a good one!
Just replace the schrader valve on that fill nipple every time you go to fill/refill the freon. @:47 It gets hot (I guess). It breaks just touching it. I learned all of this great info when a mechanic wanted to charge me $600+ (5 years ago) for a line replacement. I fixed it with a .10cent per dozen schrader valve, and vac, Harbor Freight harness and 4-5 cans of refrigerant all for less than $100. Now when I refill, It costs about $20. just for the cans.
Chevy Suburban 2500 - 2001 Vortec 8.1ltr (496ci).
My new problem I discovered today is that the blower fan was running with the ignition turned off and ran my battery down. It's some sort of control module under the glove box that has to be replaced and you can turn the blower fan off by pulling out a 30amp fuse that goes to the front AC. I haven't looked up the part yet. I'm expecting my actuators to start going any day now, so I may need to go to the auto salvage yard to part hunt.
Thanks for the video!
I wasn't sure what the problem was on my 2002. So I just replaced everything in the AC system. Everything down to the lines lol works beautifully. But stay away from UAC parts, particularly their lines!!!! I was trying and trying to get one of the lines to seal and eventually discovered that the fitting on the end was machined too short! It never would have sealed. Replaced it with Four Seasons line and it was right as rain. In fact, I think my entire AC system is Four Seasons (except condenser, that is a Denso).
Thanks Matt! This gives me a little hope on my father in laws 1998 Chevy Silverado 4x4 2500.... Someone told him that the pump is bad, but I'll go check for that pressure valve. The pump is definitely not coming on and fuse is good. Thanks for the great video! Well documented and discriptive! Also communicated well! Thumbs up AND Subscribed!
You're welcome! Never give up hope. You can always fix your problem. I think those trucks have a similar valve too. Thanks for the sub.
It may be in most of them, but for my 2003 escalade I have never replaced it still working
You are awesome..just the mechanic we all need
Thank you, I try my best
Great video. My 05 suburban intermittently does not have AC, and after some troubleshooting I believe it is either the high pressure switch, or the compressor itself.
Unplug it and plug it back in and see if it kicks on. Those sensors are junk.
@@twiztid6977420 Yea that is an idea. I was going to try jumping it with a paper clip. The high pressure switch is located behind the A/C compressor on this model so it is a bit of a pain to get to. Have to jack the car up to get behind the compressor.
@lotsoftorque3632 Yeah, you're right, I was thinking of the low side switch on the drier lol
@@twiztid6977420 Yea lol. The low pressure switch I did the paper clip test on and it didn't make a difference. The A/C does work like 90% of the time so I haven't been super motivated to get after it. Plus up here in northern New England summer is already over
blend door motors are also a big problem
My favorite is reaching up under the passenger side dash to replace the actuator. It's 5 minute job that takes over an hour and then you feel it for the next three days.
Hey some great tips; My 99 C/3500 5.7 dually dump truck will be going into a local shop tomorrow to find out were it is leaking, I did buy 1 Schrader valve for it; So I guess I should have replaced all off them, But I'll find out tomorrow where it's leaking tomorrow, But this will aid me me in the conversation. Thanks again for the very useful info. & video as well.
Yea, it sounds like you might have missed the high pressure port and the pressure switch valve. The 99 3500 is probably setup a little different.
@@MattsShop Well it turned out to be the shops equipment was the cause for a false reading, & the mechanic had to spend over $ 600.00 for new lines, & gauges with some other items he let me watch him do the leak test then showed me how it as not loosing pressure it took almost 2 cans of refrigerant, But the system is working like new again. Watching your video was very helpful as he did the whole procedure the same way you did. So I felt very comfortable watching him go thru the procedure, & the A/C system did not require anything new other than a charge. Thanks again for your video.
Gotta check the front HVAC fuse in the engine bay as it’s common to blow. If blower setting 5 stops working but all other settings work but the air could blow a little better, before changing the blower and resistor, check the fuse. Should be a small 30amp near the left rear parking lamp fuse. If you have a problem like mine, that fuse was SUPER blown. Changed it and boom bam we’re back in action.
Next time ask for an ac service kit at Oriellys. $60, and it comes with the orings and seals. Orifice tube, accumulator, valve kit, pag oil.
Have you a video on the doors acting up. I put in a new climate control panel. 2004 6.0L 2500HD. This video was the same fix on my AC i have split climate control, heat / AC for left- right. Some or one of the actuator doors isn't behaving with the control panel
Just found this video!!! Exactly the info that i was looking for. Thanks Matt!!!
I have a 2003 GMC 2500 HD the blower motor will not turn off I went through the new resistor 40 amp fuse 30 amp fuse and control module on - still have blower going on with key off? Which way do I go?
Hello
I have an 06. My ac does the blinking snow flake when it rains or I go through the car wash. Whatever gets wet will dry and it comes back on. I’ve changed the fresh air sensor in front of the radiator but it still does it. Any ideas?
A) High side valve... You need to use blue lock tight... When I unscrewed cap to check it. It unscrewed.
B) Compressor not come on to fill ? Connect the 2 wires on low side. Compressor still not coming on with 2 wires on low ; then connect high side switch wire wire to positive batt
Yea these are all great tips for sure.
The new high side valve had red loctite on it when I got it installed pretty sure.
I had an issue with mine when I got my truck my friend fixes cars and replaced what used to be did now the same issue is their such thing u can put too much refrigeration with stop leak too clog the strainer again?
Well...I have 3 of these trucks, since new
The one with the least miles...has 290k.
They all still work fine.
Perhaps regular maintenance comes into play?
You got lucky, do you live in a cold climate? That might be why. It doesn't get used much...
I picked up an 89 s10 that the previous owner ripped the compressor out of because the ac wasn't working. I wonder if could've just been this valve !
People always do this. Why???
You know what really sucks? Even the new replacement valves and fittings leak after a year !!! Manufacturers are building nothing but JUNK!!!! I had a 2000 GMC Sierra, I replaced those parts in 2011, prior to that the A/C had been working great, nice and cold. Every other year after that I had to replace them! I gave the truck to my son, earlier in 2024. It still runs good, and the A/C works fine..........until next year..........
I have a 2000 silverado with the 5.3. My AC blows ice cold, but my compressor stays on 24/7. After about 30 minutes of driving, the ac "freezes up" I thought it was strange as well that when I turn on the circulation button on the climate control it automatically kicks on the compressor, even when I don't have the AC button lit up. Any ideas on this issue?
@matts shop what would cause a 03 tahoe 5.3 to blow freezing cold while driving come to a stop and imediatly warm air ? Any help would be appreciated never been able to figure it out of all the years i have owned it
Everybody keeps having this problem. I am not exactly sure. A lot of people have suggested the A/C compressor is BAD. It runs well when the engine is at higher RPM then at a stop the RPM drop and the compressor can't move enough refrigerant. The test would be to test the high side pressure port of the system to see if the compressor is producing high enough pressures at idle.
@@MattsShop ty will be tying
so if i buy the parts i still need that ac gauge and vaccum?
Yes, absolutely
@@MattsShop thanks for that just making sure before i buy all this my ac just went out on my truck
Would this prevent for any air to go through the vents ?
Nope, look up blower fan, ac control knobs box, or ac blower resistor.
Ok with no air coming out of the vents I checked all the fuses that are for the ac and they were all good I replaced them anyways . So then I replaced the blower motor and still had no air . So I replaced the resistor and the blower . I was sure that would fix the problem and no . I assumed ok maybe it would be the controls that control the air and I tried it on 3 different controls and nothing . What else would you recommend me to try I really don’t know what else to do
Every one of those truks would be in the junkyard already if they were in Maine.Anything before 2008 has pretty much had it at this point..
You guys don't have good luck with trucks up there with all the salt and rust!
Great video, brother! My 2001 Silverado AC clutch will only engage when I jump the relay 87 to 30. I tried a relay that works and the clutch would not engage. It only engages when I jump it. The fuses are good too. The refrigerant is good. What do you think my issue may be, please? Thank you!
The safety switch is usually a problem, but it sounds like you have a wiring problem between the relay and the compressor.
Hi Matt I just came across ur video. I have a 2004 Chevy Tahoe about a year ago I took it to amco they charged me $1200 to "FIX" my a/c but about a month later the front ac stoped blowing it blows a little bit like when im on the freeway. then it stops. i changed the blower motor. still the same. Only the the back ac works. any helpful tips i should try.
Would these problems be the same for 7 4 L 1994 chevy crew cab k3500? Well not hold a charge Thank you.
It's a very similar setup, but it might leak in other spots not shown in this video.
Hey Matt, any experience with blower motor issues? I had ice cold air. I went through a car wash and it stopped working. A compressor comes on and rear AC is cold and works fine. I have changed the blower motor and resistor - actually ive tried two of each. The blower motor simply does not come on. Simple as that. I have checked fuses and I had a mechanic friend check fuses, etc.
Is it possible to install an AC on a 2006 Silverado 1500 with no AC from factory ? How much it would be?
It's probably not worth it. You'd have to take apart the whole dash to do it. A real pain!
on the yanmar tractor could you share how you repaired your charging system
I didn't lol. I just keep it on a battery charger. You can get a modern alternator off a Datsun truck that doesn't need that complicated charging system. I still need to do it.
cool it you have the alt and reg still mounted in place be great to see the cannon plug connection from the reg to the harness, I bought new both of them. Just want to connect it. awesome to know a Datson will mount without making a new mounting device
@@MattsShop
using the three point mine is elec over hyd that gets used a lot and it loves the battery now@@MattsShop
What about when your cooling fans just keep on staying on once the truck starts
Does this apply to GMT400 trucks as well?
It's been a while since I worked on one of those. It's different, but if any of the valves leak you have to fix them.
I just wonder if anyone has or does make Srader valves with Teflon? What type of O ring material is used with A/C.
I have seen A/C shrader valves made out of Teflon. Don't use regular tire shrader valves. Green HNBR orings are the best for HVAC.
Same thing happened on mine 2005 Silverado!
Yup, I figured out it's a problem on all the older Chevy GMT800 trucks.
What if the ac clutch isn’t engaging? I jumped the fuse and nothing but i guess i will try jumping that switch next
I jump the switch first. 99% of the time it has leaked too low for the switch to turn on the compressor. If jumping at the switch doesn't work there is some other electrical problem.
You don't jump a fuse...jump the relay...terminals 87 & 30.
is there a temp the air from the vents should be reaching? I just got my A/C repaired and when its really hot like high 90s outside, my '03 Tahoe only gets down to about 70 degrees coming out of the vents while idle. I have thermometer on the vent. We have taken i back multiple times but still the same issue. Any ideas?
The charge is probably low and it should blow ice cold A/C. I don't know what temperature the vents should read.
@@MattsShop that’s exactly what I feel like. But wouldn’t a shop know how much charge to fill it to? I feel like that’s too simple of an answer lol
Now when I get up to freeway speeds, it gets pretty damn cold and it’s fine. It’s just an issue when I’m idling. The fan clutch is good, but I’m thinking of changing it anyway because if I lean on the RPMs for a long time, it will cool down.
I had to fix a valve in my Geo metro but my 2003 Silverado NEVER had a leak.
I got 04 trailblazer a/c stopped last year
What state are you located at? I have a Silverado I need to look at 2000 Silverado 1500.
I will start there. Thanks man
You can do it!
Where to buy the parts ? Or Any Auto Parts Have them.
Yes, anywhere. Autozone has the parts.
@MattsShop can you do every sensor video, of the 3.5 Chrysler engine? Please, I’m your fan by the way
I'll definitely have mine replaced.
Great information! Thank you
Glad it was helpful!
Great video good explanation on what to do
Glad it was helpful!
Yes sir .... appreciate the videos
What an awesome video showcasing a well known problem and it's fix. I'm an 07' Avalanche guy with no A/C & working compressor. Thanks for the awesome tutorial. Sub'd! BTW, on my 07 Avalanche, I was always under the impression that it is a huge design flaw that they failed to include a serviceable cabin filter for the HVAC system, but I saw you making mention to one! Does it exist? 🤯 Can you include the PN#s?
Thank you! Thanks for the sub. It is a very annoying problem! They removed the cabin air filters in 2003. This 2001 Chevy Silverado has cabin air filters your 2007 Avalanche doesn't. They took them out!
2011 silverado AC has never been touched. 250k miles still ice cold. It runs almost every day.
Must be nice man 😪
@@gfloflo sometimes you win, sometimes you don't. I got lucky.
what about the oil...dont u need to add oil if system is empty?
No the oil stays in the system forever. You don't need to add oil unless you take it apart and remove/replace parts.
This is great!! Now ive been fighting with a 2017 Yukon past few years (1234yf). Are these same concepts still in play? Can I convert to 134??
Yes it's pretty much the same concepts. I know this works for R134A
What is the other unused plug near the pressure sensor plug? I've always wondered.
I'm not sure. Its extra. Hopefully, someone knows.
When you work on a/c just put new o rings and Schrader where appropriate.also my gauges somehow damaged mine
The gauges push the valve in and damage them. When you take the gauges off they leak.
My 2002 hasn't leaked from here. Oh...but it's a GMC. lol. Also, I replace them every few years, when I put it on the A/C machine.
Where did you get that small a/c can scale Sir?
It's just a food scale I've had forever. You can get them pretty much anywhere locally or online. I'd check Amazon.
Thank you Sir!
I was able to run direct power to the compressor clutch it took about 3 cans still didn't stay running without direct power
EXACTLY. Sometimes they never turn on and you think the compressor is bad, but it's not!
@MattsShop I'm having trouble with a avalanche and silverado both have good fuses and relays they hold vacuum so no leaks
02 chevy trailblazer lt ext same problem
Yup, all the old trucks do this. I discovered this problem.
You think you can send me a link or a video to find the Ac hoses and lines or my 2006 Chevy Silverado 1500
Rock Auto bro, get the discharge, suction, and liquid line. Shouldn't be over 120 bucks.
yup. my '02 avalanche had the schrader valve replaced. a year later the evaporator coil blew. Maybe the leak is protecting the evaporator coil. Maybe it was engineered that way!
Sounds like the leak saved the evaporator core. Either way it's not cooling lol
Matttttt, my ac not blowing cold when im at a stop light or just packed,. Can you make video in this 🤔
Waterpump
@@michaelmohr868 already replaced and the thermostat and fan clutch, new radiator too
If you have a cap with a good seal & it's tight it won't leak
Maybe the low side. No way the high side is sealing with a plastic cap.
It will still leak out in 2 days. I just tried that and it failed. Maybe a custom metal lid with Teflon tape would hole, but I prefer to fix the underlying problem.
How come the high and low ports are on the same line????
They have a small tube in the middle that makes it go from high pressure to low pressure. It's called the orifice tube. It's inside the tube with the nut on it between the ports.
@@MattsShop I see, thanks
You're welcome.
So what if when I press the ac button nothing happens, i just see a flashing ice symbol
Yeah i just had to loosen and tighten to reseat.
It works sometimes, but then when you recharge it starts leaking again because you have to fill it through the charge port.
What about when the leak is from the dryer
My 92 model had none of those problems. But that is when Chevy still built good trucks. The junk these days has numerous problems.
Put a o-ring on the cap- in the inside of the cap
what about a 2011?
As soon as you take one of those little vows out moisture gets into the system moisture is the worst thing for AC has to get evaporated evap to get all the moisture out 👀
At 6:15 he demonstrates how to vacuum it.
Super smart guy!!
What about the 2009
Should be a similar setup.
I have a 05 no leak still blowing ice cold
You got lucky!
so why is there 2 connects
One is not used!
cool air
I don't know but I love driving by 2014 and newer Chevy trucks and they have all their windows down guys pouring sweat and it's 90 plus degrees out because his condenser broke. I love it! Meanwhile, he's making that huge payment for what to sweat balls or do upper control arms every 20,000 and transmissions every 75-100k ye I'll pass
Mine doesn't leak, and it's almost 40 years old... Quality isn't what it used to be!
Yeah exactly, that's why there's so many mechanics now a days lol
Agreed. My 1990 454 SS doesn't leak there and neither does my 1989 Silverado.
My 2021 works like a charm.......(knock on wood)...lol.
Thanks man
No problem
It's maddening that they don't make that port replaceable like the high side. And it's double maddening that you have to replace the whole upper refrigerant line (not just the section with the low pressure port) to fix the bad port (not just bad Shrader valve).
Yes, it is very frustrating. You have to drain everything just to fix the leaks. Not fun, but once it's done it won't leak for years.
Why would you need to replace the low side one? It’s welded because the shrader valve is serviceable. The high side one is not serviceable from the factory. Throw it out and replace it with a Dorman that also uses a serviceable shrader valve.
Thanks ❤
You're welcome 😊
It’s a good idea to change the accumulator every time the system is exposed to outside air.
2000 2500 Silverado. Mine failed.
Yup, they always leak.
My 2000 Express a/c stopped working. Clutch cycles on and off every few seconds. Jumped low pressure switch and compressor comes on. Seems like freon isn't going from can into system and gauge isn't moving. Suggestions?
Sometimes you have to turn the can upside down back to upright and then it will flow in, or the compressor is bad.
@@MattsShop Thanks for the info.
@@RailFan61 before doing away with the compressor make sure you are using the Freon tap correctly! Don’t screw it down thinking “I poked a hole in it” then unscrew it all the way because then it won’t work.
Thanks again!
Plastic caps won't seal anything! It's there to keep dirt and debris out the hole! 😂😂
Yea, exactly!
Replace the valve and fill and blow.. fill and blow. Laws of fractions will have you at 75% quickly
I wish i knew mechanics here who could just do what you do, i cant trust any of them 😢
You can trust me. I'm a mechanic.
Hmmm... Mine don't do that. It simply doesn't have ac...😢