Richard S

On the 1987 S-4, I was testing for vacuum at the diverter valve (controls the air from the smog pump), when the hose somehow came undone from the vacuum side. I have no idea where it connects to, and can't see anyplace that is obvious. When I pulled it off the diverter valve connection, there was vacuum present, so it must have been just barely connected at the vacuum side. Then it just came loose in my hand, and I can't for the life of me see where it was connected. I pulled off the air-box, all the other vac connections look fine. I looked in the workshop manual, but I could only find the early car vac diagrams. Any help is appreciated.

Rich.

BC

I swear it comes from the "+" junction that comes from the throttle body area.

Bill Ball

The source is the rear port of the two that on the top of the throttle in front of the MAF. If you remove the airbox and MAF, you can get a look at the source witha mirror and with small hands or a long forceps re-establish the connection. This connection faces forward and the routing of the line is forward even though the schematic shows otherwise. I did it lying on top of the motor. It was a pain.

Richard S

There is a 5-junction piece under the airbox, all the connections there are fine. I didn't see any "+" junction, where is it located, what's it hiding under, around, etc?

Richard S

Thanks Bill, I'll yank the MAF and have a look.

Rich

Bill Ball

Rich, it does not go into the 5-way. It goes directly to the throttle body port. The 5-way goes to the other port on the throttle body top.

Bill Ball

HOLD ON.... I might be thinking of the wrong valve. Give me a minute. I will post the diagram.

Bill Ball

Here's the 87 schematic.

Richard S

Bill, I looked at that diagram as well. I know the 5-way has nothing to do with it. In the diagram, the vac line coming off the throttle body just below the MAF goes to valve "F", which is listed as the charcoal canister valve. Does the line split off, and also run the diverter valve?

Rich

BC

I was thinking of the other line. As Bill's diagram shows, it is directly hooked to the rubber single on the TB

Rob Roy

Just an fyi - and I copied this idea from someone else - when I did an intake R&R I zip tied all the vacuum connections under the intake to ensure my paws wouldn't be accidentally pulling them off again

Richard S

<<<this is me, I still can't find the f#@&ing connection. The one Bill referrenced isn't it.

Rich

Bill Ball

If by diverter valve, you mean "I", the "blow-off valve", no, it goes to its own source on the BOTTOM of the throttle body. I can't imagine reattaching that without removing the intake manifold.

Richard S

I found it as you were posting Bill. It is the single most inaccessible mother-f#@%er in there ....Yes, it is UNDER the throttle body. WTF were they thinking? I'm going to re-attach that p.o.s. without removing the intake, even if I have to grow triple jointed midget arms. Bastards.

Rich

AO