98 Blazer Vacuum Line Question

Fred Klintworth · #1 08-01-2006, 03:50 AM

Does anyone know where the vacuum line goes on a 1998 Blazer that starts with a rubber hose (about 3/8 inch outside diameter) connected to top rear of engine, runs to right of engine, connects to hard plastic 1/8 inch (approx.) hose about 3 foot long with 90 degree elbow connector on end. The vacuum routing diagram is not on vehicle. I plugged the 90 degree elbow to stop the vacuum leak; but need to know where it goes.

Tks.

billibong · #2 08-01-2006, 08:29 AM

Can you get a picture of it and post it so we have a better idea of how to help you??

muddog321 · #3 08-01-2006, 11:52 AM

2wd or 4wd and not sure which side, but 5/32" line from the PCV to the drivers side goes to a vac reservior in the fender and Ts to the heater controls (plastic) and to 4wd actuator (if 4wd) that is under the battery tray. Larger lines are 7/32". Rear of pass side the plastic is the evap vent line to the rear.

Fred Klintworth · #4 08-01-2006, 08:58 PM

Here is a picture of the portion of the vacuum line that I removed.

From what muddog321 says, I'm thinking it goes to a vacuum reservoir in the driver side fender. Muddog321, do you know what that vacuum reservoir controls, or what it's used for. Also, do you know how to access it: do you need to remove the windshielf water bottle, or anything else on the inside of the engine on drivers side?

One other thing, it's a 2wd.

Thanks for your help.

83T/A98Blazer · #5 08-01-2006, 10:37 PM

My 98 is a 4WD. That vacuum line has a check valve and tees and runs to the 4WD system in addition to the tank in the fender. The tank looks to be pretty difficult to get to, it's inside the fender behind the ABS unit. There is an access hole to the front of it, but I don't know if there's enough room to get a hand in there.

muddog321 · #6 08-02-2006, 05:45 AM

If 2wd then the vac goes to the heater controls. You can reach/feel the nipple on the reservior with your hand and I have replaced many lines on them - it takes a few minutes to feel the fitting and push a new piece of vac line on. There is enough room - otherwise have to remove the drivers side fender and thats a real pain and lots to unbolt - don't do that. A long pair of needle nosed pliers may help you but I always just use 2 fingers on the hose and a few choice words to get it connected. The res is a 3-4" can that build a constant source of vac as the engine vac changes.

Fred Klintworth · #7 08-02-2006, 06:06 AM

Quote:

Originally Posted by muddog321

If 2wd then the vac goes to the heater controls. You can reach/feel the nipple on the reservior with your hand and I have replaced many lines on them - it takes a few minutes to feel the fitting and push a new piece of vac line on. There is enough room - otherwise have to remove the drivers side fender and thats a real pain and lots to unbolt - don't do that. A long pair of needle nosed pliers may help you but I always just use 2 fingers on the hose and a few choice words to get it connected. The res is a 3-4" can that build a constant source of vac as the engine vac changes.

Many thanks for your help. I would never have figured this out without your help. The Blazer is my son's, and he's coming back over Sunday; so, I'll try to connect the hose to that fender reservoir then.

wally101 · #8 09-26-2006, 12:19 AM

Ok I also have read the post and a heck of alot of things I didnt know about my S10 Blazer 4 x 4.
I also am having difficulties finding out exactly where the vacuum hoses goes to my a/t transmission. I had to replace the 4 x 4 actuator because the diaphram was busted.
There is 3 different hoses comming from the tranny and Im sure that each hose goes to something different and that you cant just hook up a vacuum hose to each hole and it works.
One hose (vacuum) runs from the tranny to the back of the intake and from the back of the intake it goes to a round vacuum chamber. Now the actuator goes to one of the lines on the tranny and it seems to be working.....The other one has a stick in it.....(WTF) I had just bought this truck for $100 but put and engine in it that cost me $400 and with the oil and seals I have another $70 so for $570 I have a truck that is almost perfect inside and out...
I guess my question is where does each line go to and remember there are 3 that comes from the transmission...
Now the second part of my question is the Amber light isnt working on the switch (the truck has a switch to make it go into 4x4 hi/lo it blinks and goes out but if I switch the switch to 4 hi and then 4 lo in neutral it seems to goto 4 low.............Im hoping once I figure the vacuum out to which one goes where it will work correctly..........
Does anyone have a diagram for the vacuum to a 1994 S10 Blazer with a Vortec W 4.3 v6 in it...........and after this if it dont work right I will take the switch out of the tranny and have it checked if possible.....and go from there.
Thanks again for the vast amount of info on my Blazer, its just amazing what I have learded here.
Sincerely, Wally

alblogg · #9 09-28-2006, 12:26 PM

Quote:

Originally Posted by wally101

Ok I also have read the post and a heck of alot of things I didnt know about my S10 Blazer 4 x 4.
I also am having difficulties finding out exactly where the vacuum hoses goes to my a/t transmission. I had to replace the 4 x 4 actuator because the diaphram was busted.
There is 3 different hoses comming from the tranny and Im sure that each hose goes to something different and that you cant just hook up a vacuum hose to each hole and it works.
One hose (vacuum) runs from the tranny to the back of the intake and from the back of the intake it goes to a round vacuum chamber. Now the actuator goes to one of the lines on the tranny and it seems to be working.....The other one has a stick in it.....(WTF) I had just bought this truck for $100 but put and engine in it that cost me $400 and with the oil and seals I have another $70 so for $570 I have a truck that is almost perfect inside and out...
I guess my question is where does each line go to and remember there are 3 that comes from the transmission...
Now the second part of my question is the Amber light isnt working on the switch (the truck has a switch to make it go into 4x4 hi/lo it blinks and goes out but if I switch the switch to 4 hi and then 4 lo in neutral it seems to goto 4 low.............Im hoping once I figure the vacuum out to which one goes where it will work correctly..........
Does anyone have a diagram for the vacuum to a 1994 S10 Blazer with a Vortec W 4.3 v6 in it...........and after this if it dont work right I will take the switch out of the tranny and have it checked if possible.....and go from there.
Thanks again for the vast amount of info on my Blazer, its just amazing what I have learded here.
Sincerely, Wally

I am not sure as I have not had to work on my 4X4 system yet but the odd and ends I have picked up on here might get you started. On mine a vacuum line runs under the battery box to an actuator that locks and unlocks the front hubs. Then I think there is two lines that runs to the transfer case and trans.

534BC · #10 09-30-2006, 06:46 PM

Is the 3rd one the vent? (with a stick in it?) It has a wobbly cap on it?

alblogg · #11 09-30-2006, 08:33 PM

How big is this hose with the stick in it?

mdrush · #12 10-01-2006, 11:39 PM

Quote:

Originally Posted by 534BC

Is the 3rd one the vent? (with a stick in it?) It has a wobbly cap on it?

That one sound like the evap system test port. depending on year comes up near the radiator.

534BC · #13 10-01-2006, 11:44 PM

Mine is tied to the trans dipstick tube. I figured it went to the tranny, maybe the tranfer case? I'm not going to look, lol.

Linksmaker · #14 01-18-2009, 07:29 PM

Quote:

Originally Posted by Fred Klintworth

Does anyone know where the vacuum line goes on a 1998 Blazer that starts with a rubber hose (about 3/8 inch outside diameter) connected to top rear of engine, runs to right of engine, connects to hard plastic 1/8 inch (approx.) hose about 3 foot long with 90 degree elbow connector on end. The vacuum routing diagram is not on vehicle. I plugged the 90 degree elbow to stop the vacuum leak; but need to know where it goes.

Tks.

I have the same exact problem with my 99 Blazer. Were you able to find the resevor that the Vacuum Line connected too? I just plugged it and 4x4 is working fine but don't know If I need to find the end to connect too?

ZL1power69 · #15 01-18-2009, 10:33 PM

Quote:

Originally Posted by Linksmaker

I have the same exact problem with my 99 Blazer. Were you able to find the resevor that the Vacuum Line connected too? I just plugged it and 4x4 is working fine but don't know If I need to find the end to connect too?

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