Best video that I've seen yet. I already ordered the switch and actuator but I still need a couple more jack stands and warmer weather before I start wrenching on the 03 S10.
I have a 1999 blazer had my oil changed and my shop told me my 4wd was gone, I was thinking want would make the engine check light come one and 4wd light to, 5 easy things to check for the 4wd fuses, dash 4wd switches, vacuum hoses, transfer case vacuum switch, actuator. Mine turned out to be the vacuum hose. When I fixed that my 4wd and engine check light went off. I'm so proud of myself. Thankyou for all the videos. You helped me become more of a independent women. Please make more videos I'd love to watch and learn more Thankyou again 💓
That place on the check valve tee goes to the vacuum reservoir in the fender, the engine pulls a vacuum on the tank and the check valves keeps the vacuum tank at a constant level
I'm just seeing this video, trying to find the line thru the bulkhead on a 95 Sonoma off what appears to be a similar tee lol. If I see one more thread about "where dies this line go" lol (fender) but anyways goof laugh... anyone know where the vac line right there that follows the harness thru the firewall goes? I've never had a noma, I told the kid to look at hvac controls but figured I'd look around for him.. yall boys be good now ya hear
his vacuum canister reservoir is bad and caused the vac leak. Also his heater/defrost/dash vents will not work right. Under hard throttle the engine loses vacuum, all engines do, and thus the vacuum actuated hvac will not work and go from whatever setting you have it set to, ie heat, to defrost until the engine regains enough vacuum to allow control to the HVAC. The vac reservoir canister prevents that from happening.
Mine is a S10 4x4. I changed the Actuator cause it was ripped and had water in it. Nothing I got mad and here is where I am on this video. He man I looked and looked for help online videos but seemed nothing could help my problem with 4x4. I am gonna do all the things mentioned in the video. It sure doesn't look too pricey. Thanks man for a great video. thanks for helping others out!
that hose you capped off goes on the drivers side fender if you feel you can feel a nipple on the inside of the fender, it goes to you HVAC thanks for the video I like it I have 2001 s10 4x4
thanks Adam just bought a 2002 bought new tires Falken Wildpeaks will be heading into the mountains this coming wknd hoping everything works, the video was great
most helpful video I'm having the exact same problem with the check valve and broken vacuum hose on my o1 blazer . easy fix for me now also check pcv valve and hose.. thanks again from Puna Hawaii
thank you,hell ya it helped.just had same thing happed to my boys 96 blazer.same line burnt thru .and had no idear how the vacume lines worked ,now i do.lol
This helps me in a way, since I have a 1999 chevy trailblazer with a spun rod bearing that was given to me, and the transmission was able to be put in neutral and the vehicle pushed and loaded onto a car carrier, but after I had it awhile I wanted to hear the knock for myself and I just made a video of my freebee blazer, but the wheels are locked up, won't roll in the yard now, and with engine running that I can't get the transmission to do anything even when shifting,...but I didn't realize how much vacuum is on these vehicles, and below the battery tray, the rusted out battery tray, I have been removing and installing the battery numerous times, I suspect now that a vacuum hose somewhere is removed or that actuator below the battery is disconnected or damaged from battery removal and replace numerous times,...its important I work this out if I replace the engine with a remanufactured or used motor that I know what else will or will not work.....Its surprising how much vacuum lines are used, considering how much electronics were even on those late models. The battery tray is just eaten away, I have a new one, but the whole area around and below there is from mild rust to heavy rust, I may even have to wire feed weld a patch panel once I really dig around there with the remnants of the battery tray removed, and I had no idea there was a vacuum actuator there, jeese, maybe its best that way, ...easier to fix than fancy electronic solenoids, etc etc.
The vacuum line, you put a plug on, goes to a box (hidden) behind the ABS, (inside the side quarter-panel), only 6 inches away from the "T" connection. Thank you, #Adam_Hamrick for your video.
On the vacuum line right at the t .. the red lower hose goes to the hidden box and the hose to the right goes behind the distributor cap to the actuator valve.but the hose to the left side of the red hose goes where?
THANKS ADAM.A WORLD OF KNOWLEDGE. I VE BEEN HAVING PROBS WITH MY 99 S10 4X4 WORKIN,NOW I SEE MANY THINGS TOO CHECK.I HAD ALREADY REPLACE MOST OF THE VAC LINES AN THE ACTUALATOR.NOW I M TAKING YOUR ADVICE AN PUTTIN MY BUMP AROUND RUST BUCKET OFF THE GROUND ALL THE WAY AROUND,BECAUSE IT SUCKS TO CHECK THE 4X4 5 TIMES A DAY IN THE OVERSIZED PARKING AREA 8 MILES DOWN THE ROAD.. SO UP IT GOES.. AN NOW WITH YOUR HELP AN THE HELP OF YOU PEOPLES COMMENTS. WHICH I WILL BE REFERING TOO ALL THE TIME INCLUDING YOU VID..
BY THE WAY THIS IS A NEW AREA FOR ME AN IM NEVER TOO OLD TOO LEARN..I ALWAYS TELL MY WIFE AS I LOOK SOMETHING UP ON RU-vid ,THAT IM GOING TOO TAKE SOME CLASSES , DO SOME STUDING..HA..
OH UNDER A DIFFERENT SUBJECT ,MY AWESOME DAD THAT PASSED AWAY LAST YEAR.WOULD SPEND ALOT OF TIME ON GOOGLE EARTH..AS I WOULD CALL OR GO SEE HIM 2X A WEEK I WOULD ASK HIM SO DAD WHAT HAVE YOU BEEN DOING THIS WEEK..HIS ANSWER WOULD ALWAYS BE ON VACATION,I WOULD SAY REALLY WERE DID YOU GO ON VACATION TOO. AND THEN HE WOULD TELL ME EVERY COUNTRY HE VISITED WITH OUT EVER LEAVING HIS HOUSE...ON GOOGLE EARTH...
Since all tbe comments are 3+ years old ill add this for thr next guy (thankfully plenty added this years ago) but dont cap the tee lol, tbe hardline you see goes to hvac and where he capped goes to thr resevoir inside tbe driver fender behind the abs modules bracket (windshield side) lol. Dont cap.
I replaced this part as well as the actuator which was destroyed when transmission fluid leaked through the vacuum line. The new switch did not prevent the TF from leaking and it destroyed a 3rd and fourth actuator until I solved the problem by installing a check valve that allows vacuum but not fluid from the transmission. In order to revert to 2wd, I have to manually release the vacuum. I do this by having a dual ported check valve. I have a vacuum line extending out with a plug in it. I remove the plug for a second to release the vacuum after pushing the 2wd button.
at that point, why not rig up a lawnmower throttle for the front axle fork haha. Im hoping all I have is dry rotted lines, which are crumbling in my fingers. hope I dont have the dreaded input shaft seal leak on the Tcase
thanks man I just got mine for $300 but I need a new windshield and tires. I can hear it shift into 4x4 but the front tires still don't spin. I think it's probably the same problems you had. thanks alot I'm going to check right now
jaguarpaw5 it is probably the actuator under the battery and if it is not the actuator your cable might be stuck going to the front end and if all else fails the gear might be run off in the front end
The thing that you plug in / capped... It's called and goes to the " Vacuum Canister Reservoir ". I believe they changed it to the " Hidden Driver Fender " after 1996/98 on?, or if your " Relays " are NOT on the Passenger Side or in the Glove Box. If you see the Black Big Fuse Box / Relay under the Hood on Driver Side, then you know they changed it and it's " Hidden " on Driver Side Fender.
When that vacuum switch you had in your hand takes a shyt? It leaks transmission fluid up into the diaphragm & the transmission fluid rots the, diaphragm. I'm thinking it probably eats at the vacuum lines, as well? I'm going through this with the 4wd on my 96 Blazer, currently. I gotta get me that 3 hole vacuum switch. I already replaced the diaphragm. That shut my check engine light, off. I put a BADD switch in mine til I can get a NEW one. It's jammed all the way CLOSED to keep transmission fluid from going into my new diaphragm. I just still don't have 4wd, at the moment.
I love these trucks, my ZR2 is a 02 blazer, but the vacuum operated 4wheel drive absolutely suck, just a crappy design. That alone is the only complaint I really have with it.
+Chuck Kelly - #1= It might be your Trans Case Switch. #2= It might be your Transmission Fluid Flooding. Why? There is a Rubber O Ring between your Transfer Case and Transmission.... When that goes bad.... It leaks into the Transfer Case... When the Transfer Case is full..... The Vacuum " SUCKED " that into the Vacuum Line. By doing that, the Line got Flooded and Vacuum Loss, causes NOT to be working correctly! NOTE 1: TO FIX:.... Under the Hood.... Find the Vacuum Line that is in the " Middle " of the Engine, close to your Wiper.... That is the Line.... Take that off... Then take the Line that is " Under / Close " to your Transfer Case Off.... IF YOU SEE DRIPPINGS..... You have a Leak.... Go back to under the Hood... Take that Line and BLOW on it..... You should see bunch of Fluid coming out..... That means you are freeing the Vacuum Tube from Transmission Fluid. NOTE 2: REMEDY.... If you have Trans Fluid Leaks... Try a Bottle of Lucas Transmission Sealer..... This will help you for a while. :)))))))))))))
Ok so I’m confused, I bought a Sonoma with the dash button switch and 4x4 doesn’t work. And I looked under the battery and there is no diaphragm or mounting for it and it looks like it was never there. But it has all the valves in the front axle and on the transfer case and I have the original window sticker for the truck and it come with 4x4 from factory. Did some models come with a fully electric system?
Thanks for the video and by the way my 1999 Blazer just now is showing "Service 4 Wheel Drive" light on the dash. It will work for a short while when i just start the truck up in the morning then the Service 4 Wheel drive light will come on and then it will not change out of 2 wheel drive. Do you have any comments?
@Tom Gregory - I used Fuel Lines as Vacuum Hoses... It worked a lot better than those cheap Vacuum Hoses. I also made a Video under my Channel recently as much details as possible on the routing... Check it out... You might find something useful!
My issue is I have a 99 Gmc jimmy and I just replaced the 4x4 selector switch cause the other one wasn't lighting up..My question is when I put it into 4hi or 4lo it engages and it disengage.But when I push the button the light doesn't stay solid but it flashes and do know some vehicles are designed to flash.Now there is no 4x4 service light on either.Now is my truck designed to flash when in 4hi ?or could this be a bad switch or something else??I just bought this jimmy 2 months ago and it was well kept but this issue bothers me..Please help me if you can..
On this particular S10 that I worked on when you push the four wheel drive button for high or 4 Low at flashes as it goes into what you selected.. and then stay solid once it's in that position..
A little late but if you place the index pin at 12 o’clock and go clockwise: At 2:00 it’s to the vacuum source (firewall area); 6 o’clock 4WD actuator, and, (3) 10 o’clock position, it’s vented to the outside with the unique restrictive cap at the end of that hose.
So i just bought a 98 blazer 4x4 dosent work and i know a few lines are dry rotted. So basically just replace all the vacuum lines and the actuator and the switch. And it'll be fixed right lol
I had the same problem. I put in a new diaphragm under the battery tray and new vacuum lines all over. The line from the diaphragm that runs through loom to the vacuum switch on the transfer case is very important to change. You have vacuum but not enough to make it fully engaged.
The sizes vary. OEM hoses are stamped on the outside of the hose. Generally: *Intake Supply Line:* 7/32" ID, 7/16" OD, L = 20" Designation: 7/32 GM6148-M 121594 ABG *Hoses/Lines to transfer case:* 5/32" ID, 5/16" OD, L = 7 feet (total of three lines) Designation: 5/32 GM6148-M [121594 ABG] *To vacuum reservoir:* 3/16" ID, 5/16" OD, L = 8"
This is about the shittiest way I've ever seen to engage 4x4. This was deliberate by getting rid of the reliable physical link to the axle via a lever they would sell parts when something would always fail. Vacuum lines are a terrible way to actuate anything because they rot out. If you want to get rid of the vacuum and actuator headache just install a manual cable pull to give yourself a direct mechanical link to the axle.
Totally agree. Detach cable to front diff from vacuum actuator under battery tray. Manually pull cable and clamp off to engage front diff. Transfer case still controlled from dash switch. That will get you going. Permanent fix is a manual push/pull turn lock PTO style cable retrofitted from under the dash and attached to the same cable. Leave all the other vacuum lines and wiring hooked up. WTF made GM engineers think this goofy vacuum system would keep working?
@@5000mileswallow Hehe, the KNEW it WOULDN"T keep working! The space cleared from the old lever engage on the drive shaft hump they filled with that cassette player that covers the entire hump. Worthwhile exchange right? The first gen Blazers and S-10's were the best and simplest IMHO.
