Recirculation vacuum hose

Found a mystery vacuum line between the heater hoses. Did my homework and found that it's for recirculation (which does not work on my car). Traced around and found two mysteries that I'd like help with:

1. It's routed all the way around the battery, and comes out near the starter, via a couple of plastic pipes that are destroyed on my car. Why all this distance?

2. Where does it terminate? I couldn't find a fitting near the vacuum pump, but maybe I didn't look hard enough?

Behind the battery is a solenoid valve.

Without looking, I'd think there's also a connection at the vacuum pump, itself.

-Todd

Todd's right, behind the battery is a switchover valve. On my car there's a connection there for a reservoir. There's also a connection to the vacuum pump. I'm not sure that original TDI cars got the reservoir though.

Steve

Ok, I found the solenoid, but still stumped as to where the hose terminates. Upon closer inspection it appears *possible* that the brake booster check valve has two vacuum nipples, one of which is broken off on mine (the other goes to the "egr frequency valve" near the airbox and is intact), but it's hard to tell as that whole piece is old and scratched up. Can anyone look at theirs and tell me what's what?

Coming directly off the vacuum pump is a large pipe which feeds the booster, but closer to the pump there are two nipples that feed the EGR and recirculation solenoid. On the other end, the recirculation diaphragm is under the right side of the dash all the way against the passenger's side wall, and you'll have to remove that lower trim panel to see it.

rite as of now one/first thing id say, is your recirc may not be working just cause this vac circuit isnt working correctly. do you still have both nipples, that come-off vac pump? opening here is straight air to crank-case. its not really that difficult as far as a/the set up, just such as the solenoid doesnt seem to be near, or apparent to a vent or vacuum system, gotta luve does engineers, at times, tho,

My vacuum pump just has the one big pipe, and the EGR is fed off a check valve connected to that pipe. Check valve has only one smaller nipple on it, like below. Can't figure out where the recirc is supposed to go, on this end.

On the other end, the recirculation diaphragm is under the right side of the dash all the way against the passenger's side wall, and you'll have to remove that lower trim panel to see it.

Click to expand...

Thanks for that info. I'll see if the under-hood stuff is all that's wrong with it before dealing with the actuator. That hose looks annoying to replace.