Does anyone know what this valve is supposed to do? It has two wires to it and a vacuum hose. But the hose is only about a foot long and then stops unplugged. The number on the side is EAC4100, when I search for that I find them for sale, but no descriptions of what it does. Its in the right rear of the engine bay.

 

I think it may be the solenoid in the upper left of this diagram. It's part of the vacuum advance system.

Jon

 

What market car? My canadian spec car has one of those but it is sitting under the intake manifold, its part of the timer that limits vacuum for a 60 sec or so after start.

 

Gareth
I think that is the vacuum line to the vac reservoir, non-return valve. The vac reservoir is under that plate. It should be connected to the A bank vac spigot on the end of the inlet manifold. It may be joined by other vac lines.
It is certainly a vac line to something under that plate, anyway!

 

I’m asking about this part circled in red. It’s heading off towards the A bank, I’ll see if there’s a spot for it. The car is a US spec ‘87 V12

 

That is the vacuum advance dump valve, I think, repeat think. Its purpose is to dump vac from the vac capsule under cetain conditions, but I know no more!

 

Mine had 2 of them, one was the dump solenoid unit for emissions junk, that was blocked off waaaay back.

The 2nd was the dump for the Cruise Bellows.

The Vac Advance Dump Valve had NO wires involved at all, just worked on differential vac on each side of a diaphragm.
I think???? I have a snap of it somewhere. If I find it I will come back.

There is another EAC4100 inside the cabin, on the LH side of the A/C assembly, and has somethong to do with recirc versus fresh aoir.

 

jal1234 is right. It's item number 6 (also valid for Canada), and it goes into the vacuum regulator. NLA.

 

Thats exactly what mine has(canadian). It wasnt connected when i got the car. The vac advance delay/timer wasnt functioning. I reconnected all lines as per original and it works now(i think by now most have been disconneted)