Vacuum Hose Help

[AHall]

Hello,

I am having an idle problem. My 1993 240 will not idle. When the ungine is cold it idles a little high but does not fluctuate. Then as the engine warms up the idle starts to fluctuate and then stalls out. I serched for vacuum leaks and replaced the engine coolant temperature sensor, but no luck. I then removed the small vacuum hose that is connected to the engine air intake manifold near the back of the motor, and the enigne seemed to idle fine. Can someone tell me what this hose is connected to? I can see that it goes into a T with another hose coming off and running between the firewall and engine and the other hose goes into a hardline that disappears under the air intake manifold. Does this go to the carbon canister.

Any help would be greatly appreciated.

Thank You,

[AHall]

Also does anyone have a more detailed picture of the vacuum hose layout other than the one in the service manual? It does not show details of where each hose goes after they enter the hardlines and after the hose enters the T near the back of the engine close to the EGR valve