Gday guys n girls I have a long vacuum line coming up from the tranny tunnel on more recent purchase, 91 xj40. No idea where this went, but apon replacing a headlight on the passenger side (rh drive car) i noticed a gadget adjacent to the air cleaner and a bit below it with two vacuum outlets, one of which was connected and one which wasnt! So Ive decided this is the home of my errant vacuum line because its going in that direction and is the right length. The engine still starts after sticking it on, but can anybody tell me what that thing is for and what does it use vacuum for??

 

G'day mickvic,

From your description of the hose, it could be part of the evaporative emissions system and could be a hose that runs from the fuel tank to the pressure reducing valve at the carbon canister inside the front left fender arch liner. See the diagram at the link below:

Carbon Canister Bypass System - Parts For XJ6 (2.9, 3.2, 3.6, 4.0) from (V)500001 to (V)667828 | Jaguar Classic Parts AU

The device you describe near the air cleaner could be the Speed Control Actuator Pump, or possibly the Dump Valve. See the diagram at this link:

Speed Control Actuator - Parts For XJ6 (2.9, 3.2, 3.6, 4.0) from (V)500001 to (V)667828 | Jaguar Classic Parts AU

Another possibility might be that it is supposed to connect to your heater control valve, but it sounds like it is too long for that.

Cheers,

Don

 

Well the part I am talking about is the speed control actuator pump but the line i have connected to it may be the vacuum hose from the tank thanks for the diagrams, in it the speed control actuator pump has two inlets pointing down and one vacuum line connected. Ill check the set up again and try and get the right lines connected to the right bits. Thanks again for the diagrams.

 

Id say its the vapour line come up from the fuel tank and meant to go on to the canister. Its just sitting loose in the engine bay.

 

Hi mickvic,

Judging from the parts diagram, your Australian-spec car may differ from our U.S. one, but below is a link to photos that may possibly help you figure out where that loose hose may go:

Welcome to Jag-lovers - Members Photo Viewing Page

Cheers,

Don