!984 vacuum tank question.
Thread Starter
Racer
Joined: Aug 2014
Posts: 269
Likes: 4
From: Bossier City Louisiana
!984 vacuum tank question.
My manual is pretty vague on this but I am trying to find out where the vacuum lines go from the T-fitting that's connected to the manifold. I know that one end connects to the manifold and another pulls the vacuum from the vacuum tank. I just don't know where the line is and where it connects to operate the HVAC vents and other vacuum operated parts.
I can see one end that will go to the heater control valve in the engine compartment and will plug it for now as I don't have the heater control valve installed yet. I was pretty sure there was a vacuum fitting that feeds through the firewall with the ECU wiring harness but can't find it yet. It probably broke off at some time as this is a used harness but I can't find the feeder line that comes from the engine vacuum.
Help!
Russ
I can see one end that will go to the heater control valve in the engine compartment and will plug it for now as I don't have the heater control valve installed yet. I was pretty sure there was a vacuum fitting that feeds through the firewall with the ECU wiring harness but can't find it yet. It probably broke off at some time as this is a used harness but I can't find the feeder line that comes from the engine vacuum.
Help!
Russ
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
I believe your vacuum connections are the same as mine in 1986.
My vacuum check valve looks like this:
The right angle vacuum fitting on the right end goes into the engine wiring harness and to the HVAC system. The hose going off the side goes to a T near the battery. The T splits off to the cruise control servo and the straight through part of the T goes to the vacuum tank.
My vacuum check valve looks like this:
The right angle vacuum fitting on the right end goes into the engine wiring harness and to the HVAC system. The hose going off the side goes to a T near the battery. The T splits off to the cruise control servo and the straight through part of the T goes to the vacuum tank.
Thread Starter
Racer
Joined: Aug 2014
Posts: 269
Likes: 4
From: Bossier City Louisiana
Thanks. They look similar but I just can't find the vacuum line in the wiring harness. Your picture looks like it should come out somewhere under the distributor. This is my first restoration of an 84 and I have everything back in the engine compartment but I never thought of a vacuum line threading through like that.
I have a few ECU wiring harnesses. There is a vacuum line that is taped to the interior portion of that harness to the ECU that will fit a vacuum line coming from a line somewhere in the heater core box but the other end of it is open. Again this line is in the passenger side.
There just isn't any diagram of the vacuum lines that control the HVAC that I can find. Nothing that shows a line coming out of the wiring harness that plugs into the one way vacuum fitting that comes from the manifold, to the vacuum storage tank. My 84 vette does not have cruise control.
Thanks for the picture though. It is a start.
Russ
I have a few ECU wiring harnesses. There is a vacuum line that is taped to the interior portion of that harness to the ECU that will fit a vacuum line coming from a line somewhere in the heater core box but the other end of it is open. Again this line is in the passenger side.
There just isn't any diagram of the vacuum lines that control the HVAC that I can find. Nothing that shows a line coming out of the wiring harness that plugs into the one way vacuum fitting that comes from the manifold, to the vacuum storage tank. My 84 vette does not have cruise control.
Thanks for the picture though. It is a start.
Russ
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Check out this picture from Agent 86's car. It shows the vacuum line that goes into the engine wiring harness and the right angle rubber coupler that goes on the end of the vacuum check valve:
Thread Starter
Racer
Joined: Aug 2014
Posts: 269
Likes: 4
From: Bossier City Louisiana
Thanks guys. I pulled the distributor out so I could really check the loom out and found the vacuum line. That is a big relief. I was broken off as seems to be the case most of the time but if the rest is intact, I will be a happy Corvette owner.
Russ
Russ
