Cadillac Catera and Cimarron Forum Discussion, Vacuum Line Question in Past Cadillac Vehicle Discussion; I'm trying to finish up a timing belt / valve cover seal replacement job and ran into a little problem.
I'm trying to finish up a timing belt / valve cover seal replacement job and ran into a little problem.
Although I've had the intake plenum, intake manifold, etc., off this car in the past to replace the oil cooler, I don't remember seeing the "stub" of a vacuum line in the attached image.
One side of that "T" goes to the little vacuum tank that sits low on the intake tubes (down by the radiator). The other side of the "T" goes to the passenger side of the firewall. The stub just in front of the screwdriver blade is open to atmosphere - I've removed the "T" and verified all the paths are open.
Surely this isn't correct - but I can't find any other loose vacuum lines which might attach to the stub. I have a factory manual set, but can't find a vacuum routing diagram in there - if somebody can tell me what this should be connected to, or point me to the diagram in the manual set, I'll be forever grateful.
Found it. That is supposed to connect to an extension of the vacuum booster check valve. The extension snapped off. I'll either have to buy a new check valve, or try to repair this one by bonding a short piece of tubing in there.
Happens all the time.
You need about a foot and a half of some special vacuum hose and a new check valve.
You have to slice the sections of old tubing off the ends and cut the vacuum hose which has a wire inside it to keep it from collapsing.
The new check valve comes with a small white cap you need to break off for the 2nd vacuum line. (some cars don't use the 2nd line so it is capped)
It is a pain in the butt really.
Plus the hose is fairly pricey.
I replaced one last week and another one today.
I repaired it by drilling the remaining stub out to 1/8" to accept some 1/8" OD vacuum line I had in the parts drawer. I bonded this in the check valve, leaving about 1" exposed. And then used some rubber vacuum line to couple that to the existing "T". Works great.
As to the purpose of the line: because it goes to the firewall, I suspect it supplies vacuum to the HVAC system. Once I fixed it, I quit worrying about the function!
This is the vac feed for the multiram (get it working and you get MUCH more go unbder 4000rpm) and the internal heater controls....
If I see a broken one I drill out the stub on the valve to the same diameter as a piece of teh vac line, I then liberate a 1inch (note I use the very old fashioned units here for clarity ) piece of vac line from a slack section and insert it into the hole and apply an epoxy around the outer edge (rough the plastic first)......jobs a good un....