Hi to all and thanks in advance for all the help.

I have a 98 Blazer with the non auto transfer case. I replaced the transfer case vacuum switch 3 days ago as my front driveshaft was not disengaging - the switch was allowing vacuum to pass all the time. Today I had the problem of no 4x and the HVAC controls stuck in the vent position. I traced it back to a faulty hose that had sucked up transfer case fluid due to the bad switch and collapsed.

I now have everything working as it should and I am beginning to replace all the vacuum lines as the oil really ate them up. (Switch was faulty for a long time.)

I now have a question about what hose goes were. I'll try to describe everything as best I can.

1. Hose from manifold to a vacuum check valve with 2 outlets. This is near the power brake booster.

2. One hose splits off the valve and immediately splits into 2, with one side running to hard plastic line for the HVAC and the other I would assume to the transfer case switch.

3.There is the mystery hosewhich goes from thecheckvalve out through the inner fender. Where does this hose go?

I would appreciate any answer on the mystery hose.


EDIT: Please move to General Tech Help.

 

Anybody?

 

I think there is a vacuum ball or the like mounted inside the fender. You should probably call a GM dealer to be absolutely sure. I had one once(a Blazer) and if I understand correctly what you're saying...This Blazer was missing it. I bought one at that time from GM(think I still have it somewhere) but for some reason never changed it(I don't believe). Can't remember if we capped off the line or what-this was probably five years or more ago. I would check with GM and if you're keeping the truck-try to do it right. I don't believe it'll cost all that much. Jerry

 

Yep-I checked with the dealer today and it is a vacuum reservior. Mine is there but I don't know how the hose attaches to it. I looked on the fische at the dealer at it appears that the hose just force fits in a hole in the unit. Seems kind of wierd.

I have to replace the hose but I can't really see what's going on down there because of the ABS junk.

 

I have posted this a few times in the last few weeks, but search seems to be useless at this point in time. Anyway, here is a diagram that should answer the questions you have asked.

 

Thanks for the reply swartlkk. The only difference I can see in mine is that the cruise appears to be all electronic - no vacuum to the unit at all. Doesn't have the big canister like the old vacuum controlled cruises.

Anyway does anyone now how that hose fits in the vacuum tank? The dealer's diagram really doesn't show much.

 

Yeah, I probably should have mentioned that was for an earlier Blazer. The rest of the schematic shows it and I have not been successful in finding another equivalent diagram for the newer trucks.