Hi all - I have replaced most of the old dry cracked vacuum hoses under the hood of my 1991 L98 automatic coupe, but there is one line giving me trouble.

It's connected to (I think) the power brake vacuum booster, when I try to reach down to pull it off the one unseen end, instead of a solid resistance it feels like I am pulling on a "bellows" of some kind.

Is it safe to just pull until the line comes off (what I assume must be a fitting down there? can't see it...) or do I need to dismount the power brake vacuum booster from the firewall completely?

Thanks!!

The booster has a plastic check valve the hose attaches to. Tugging on the hose will sort of yank the check valve out of place.

It surprises me you can't see where it connects. On mine the check valve is plain as day. It's not blocked by the ECM is it?

You ARE pulling on a larger diameter vacuum line right (~1/2 OD)? Or else you're confusing the booster with something else.

Try twisting it to break it loose. The ones that are really stuck in place require cutting the hose lengthwise through the braids.

There's also a cruise control hose that goes through the firewall below the booster, maybe that's what you're tugging on. This one goes continuous through the firewall with a bit of glue and connects up by the pedal linkage. Once you remove it, it's much harder to get a new one back in there.

My bad -- it does appear to be the cruise control (small outer diameter) hose that is the bad one -- unfortunately as you noted it looks like it goes all the way into the firewall.

I may be able to just use some kind of joiner to splice in a good piece of hose under the hood? Thanks all...

Oh, yea. You can splice there. most auto part shops sell these little vacuum T's and couplers.

there should be a vacuum check valve just to the left of the distributor that that line goes to. Mine went bad, and the cruise quit working. You need it to properly keep the cruise working.
cough cough
I just happen to have another one of those check valves for about $10 shipped.

Hmm. Maybe that's why mine doesnt' work. Not that I've ever had a need for cruise control.