twright5

Hi,

I am a real novice here, but I have a question that I hope someone can address. I have a 1995 Blazer. When I select the Vent setting on my ventilation control, I get no air from the vents. I do get airflow to the floor when I select Heat, and airflow to the defroster when I select Defrost. It seems like I have a faulty switch or relay. Can anyone tell me what part I would need and if the replacement is relatively easy? Or is there something else I could test? I googled for this and found a suggestion that I should disconnect the battery for 30 seconds or so to see if the switch resets itself. It was suggested that the switch might be lgoically stuck in a bad state. Any suggestions?
Thanks!

Rick Norwood

Look under your hood and find the Black vacuum ball. It is about 6 inches in diameter and usually is on the passenger's side of the truck. See if the vacuum line (or Lines) have fallen off or if the ball is cracked or broken. if so, you've found your problem. If you need to replace the ball, go to a wrecking yard for the replacement.

twright5

OK...found the ball. It was mounted to the hood on the driver side. There was a line loose, but I cannot see where it should connect. Can you please try to tell me where it goes? The tube has some printing on it indicating that it is 7/32 AGB. It feeds from the ball along the firewall towards the A/C, but I cannot see where to attach it. Any help is appreciated!
Thanks.

Rick Norwood

Are you sure you found the right ball? I've never seen one mounted to the hood. It should be approx. 6 inches in diameter.

I would look around the intake mainfold to see if there is a fitting without a tube. There are bunches of fittings and tee's all around the area. How many tubes are on the ball?

BlazerLT, help me here since you own a '95.

twright5

Not entirely sure I found the right ball. I just measured it and it's about 5 inches in diameter. There is one hose connected to it and it tees off into 2 lines. One is disconnected and the other is connected.

I also tested the airflow in the car again. It seems that no matter what setting I choose (vent, heat, AC, etc.) air blows from both the floor vents and defroster vents.
Thanks!

Rick Norwood

I just looked on my daughter's '93. Look on the back side of the intake plenum. (On My 93, the word "Vortec" is written across the top.) Just underneath the top edge, but above the distributor there is a short nipple that accepts the vacuum line. It is about 3/4 of an inch long. You almost have to crawl on top of the engine to see it, but the vacuum line should connect to the intake manifold somewhere back there.

On my 93, the tube comes off of the ball and goes into more of a "Y" fitting rather than a "T" fitting. The down leg of the "Y" fitting has about 1 inch of vacuum line on it where it attaches to the back of the intake plenum as I described above. This hose is/was very easy to pull off. Please describe how yours looks, do you have a "Y" fitting and a short piece of tubing attached to it, or is the other end disconnected? Once you find the right place to connect this vacuum line, your problem should be solved.

twright5

Thank you so much! I love the internet! That did the trick!
It was a Y-fitting by the way, but now that point is moot.
Thanks again.

Rick Norwood

Sweet!

Everything is working O.K. now? Did you have the short piece of vacuum line coming off of the "Y" like I described? I have had to cut a small piece of vacuum line and replace the short leg a few times due to the heat. If you notice that yours falls off, you might do the same.

Rick

cubanlorenzo

i have a 95 too and my vaccumn ball is attached to the hood on teh drivers side as well..

twright5

Yep, everything is now working. Yes, my lines are just as you described. I will keep your suggestions in mind.

Rick Norwood

On My '93, the Vacuum ball is located on the passenger's side fender wall. On my 2000 Jimmy SLE. I haven't found it yet, it isn't on the hood or the fender wall. So, some time between 1993 and 2000, it appears that Detroit changed designs a few times to keep us guessing.