AAN Engine Vacuum Hoses and Related Devices

[chris]

100 s4

reading this thread with interest, having just bought a 100 s4 avant, it does not want to really go!, i can find no obvious boost leaks pressurising the system and the remote boost gauge is only showing, 15 psi flat out in 3rd, otherwise it starts and idles ok,, plus a temp gauge under reading , and a non running heater motor, but the ac pump works, [fan motor]?
car is L reg from istoo and previously pre owned by other bods on this forum

[S2central.net]

scrap the lot!!i dont use any..

Uhhhh fine - knock yourself out. Just remember to vent the tank fumes so you don't get excess pressure on a hot day. Motronic has map to control evap / n80 in a nice way - very elegant compared to half-baked afterthought in vems for example.

[A80Avant]

i always thought that the tank already has a little hose that excess fumes can be released to avoid pressure.

[UrS4boy]

i always thought that the tank already has a little hose that excess fumes can be released to avoid pressure.

The stock fuel system is completely closed, no venting to atmosphere. Venting to the carbon canister but not the atmosphere, at least this is true for the C3 and C4 Audis.

http://forums.quattroworld.com/s4s6/msgs/21014.phtml

[UrS4boy]

reading this thread with interest, having just bought a 100 s4 avant, it does not want to really go!, i can find no obvious boost leaks pressurising the system and the remote boost gauge is only showing, 15 psi flat out in 3rd, otherwise it starts and idles ok,, plus a temp gauge under reading , and a non running heater motor, but the ac pump works, [fan motor]?
car is L reg from istoo and previously pre owned by other bods on this forum

15 psi from an old tired K24 with no chips is about right. That said you still might want to do a boost leak check. Try this:

http://forums.quattroworld.com/s4s6/msgs/29530.phtml

[chris]

100 s4

15 psi from an old tired K24 with no chips is about right. That said you still might want to do a boost leak check. Try this:

http://forums.quattroworld.com/s4s6/msgs/29530.phtml

thanks for that, , it has a stage 1 mtm chip set, so it should be running my 200 3b conversion[mtm] chip , fairly close, thanks for the link, i am on it,,,,that said the turbo does whistle a fair bit could be tired?

[jevrem]

I know about the fuel reg and ecu line, ive just snapped a pic of the hose im on about, the feed from the manifold splits at that black t piece, then one goes through the bulkhead like you can see in this pic and the other goes to the right and connects to a black plastic line (diff?)

Maybe this hose goes for control of locking the diferencial. You can unplug the hose and try to block the rear diferencial. If it can not be locked than the hose is for the the diff.

[martinjs]

It goes to the climate unit.