HELP! Where does it GO????

[bl36sr]

On my 84 there is a black hard plastic vacuum line on the passenger side that is disconnected. The line is in the ECM wiring harness. It does not plug into the A/C heat controller all those line are where there are supposed to be. I have included a picture of the harness and line. If anyone knows where this line goes please let me know. Thanks!!

 

[WhalePirot]

On my 84 there is a black hard plastic vacuum line on the passenger side that is disconnected. The line is in the ECM wiring harness. It does not plug into the A/C heat controller all those line are where they are supposed to be. I have included a picture of the harness and line. If anyone knows where this line goes please let me know. Thanks!!

AFAIK, those hard plastic lines are for the HVAC vacuum control; one end or the other (control head or operating end, including under the hood, at the firewall, fwd of the inside-mounted ECM).

Does all of the system work okay?

 

[bl36sr]

Where does it go?

Thanks for your reply but the two that go to the control are accounted for. I know where those connect, this line is all by itself comes from the engine compartment. I have the 84 service manual and have found all the vacuum lines other than this one. It is the only vacuum line that is in the ECM harness. The dash is all apart at this time and car not opperable so I can't check under running condition. I was hoping to find where it goes before I put everything back together.

 

[WhalePirot]

From the 8A manual supplement

hope these help



Sorry the quality is not better.

 

[Fast Freddie]

here is another one.

View attachment 84hvacvac.pdf

 

[bl36sr]

Where does it go??

Thanks to all who sent vacuum diagrams and offered suggestions. I had previously gone over the diagrams in my service manual. I think I could connect all the AC/heat vac hoses from memory at this point but unfortunatly my unconnected hose is not among them. I believe that the diagrams show all the HVAC hoses, so I guess this line is not part of that system. It's too short and to small for the cruise control line that one is there and connected to the brake switch. The other end of the unknown line is connected as there is resistance when air pressure is applied. I may have to wait until I get the car running and see what doesn't work.

 

[WhalePirot]

Mine has one, underhood, near the heater bulge, that melted years ago and I saw no difference in operations. I've looked and looked to see what it is/what it does.

Good luck with yours.

 

[boomdriver]

Mine has one, underhood, near the heater bulge, that melted years ago and I saw no difference in operations. I've looked and looked to see what it is/what it does.

Good luck with yours.

That one was the heater/water control valve that opened or closed the water flow to the core when the a/c or heat was used.

because the valve leaked and was damn expensive, I deleted mine and plugged the vac line. No noticable change in a/c cooling with hot water in the core all the time.