Upper intake vaccum & plumbing
 

I have a Vortech intake manifold in my '93 GT. There is a vaccuum hose that runs from the front of the upper intake manifold down to the black canister in front of the engine in the passenger side.

I had some work done to my car and i noticed that air was being sucked into the manifold at such a great rate, the walls of the hose were being crimped.

Should air be going into the manifold or should air be going out of the manifold & into the black cannister?

Re: Upper intake vaccum & plumbing
 

"vacuum" hose :D

Re: Upper intake vaccum & plumbing
 

The black canister is a charcoal box used for emissions. I am assuming that air would be directed to the charcoal box and filtered in order to lower the emissions on the vehicle.

I may be wrong though.

In any event, if you have to have the car emmisions tested, that hose being crimped would definately show some negative result.

Re: Upper intake vaccum & plumbing
 

You are missing a part in your vacuum hose called a purge solenoid. It will allow vapors from the carbon canister to be drawn in to the intake to be burned occasionally, but not all the time. It is roughly an inch around and 3-4 inches tall, has 2 fittings on the bottom and 2 wires out of the top. Your connector should be around there somewhere. This is all from memory, so if something doesn't sound right, let me know and I will check into it.

Re: Upper intake vaccum & plumbing
 

Gas fumes from the fuel tank are directed (hence the reason for a pressurized fuel tank cap) to the charcoal cannister via that small diameter harder plastic line popping up in to the engine bay near the passenger side shock tower. As others have mentioned, occassionally a purge solenoid opens allowing the excess fumes to be sucked in to the intake and burned to reduce harmful emissions. When that solenoid fails (or is missing), you've got one huge vacuum leak.