This object is coming out of the back of the intake manifold. It has a 3/4" hose coming out of it that is disconnected. I can't figure out where the hose goes to. Is this the ACV? I have stock cats. I don't think I should block it off with all emissions still intact. This is on the passenger side of the car close to the exhaust manifold.

I have the object circled in red and the hose end in yellow.





Kev

 

It might be a stalactite.

 

That object in question is the fresh-air tube that goes to the cat itself,the catalytic converter will get clogged up if you do not reconnect it,there should be a "hard line"/metal pipe that is in the proximity of it that goes back to the cat,if not go to the hardware store and get some copper pipe that is around the same size and run it back to the cat and use a similar rubber tube to connect to the cat.

 

Would that be why my car backfires frequently?

And would it cause the idle to run like it has a vaccum leak?

Kev

 

That is mainly just the rotary thing though,you'll learn to like it,if it is too rich it will more,alot of things contribute to that.

 

Bump.

Does the cat fresh air line cause a vaccum leak at idle if left hanging?

Kev

 

so THATS what that is. wondered if it was important, my headers burned through the rubber hose where it was touching it. no cats, no worries.

 

Bump.

If I were to put something in that hose to block it off would It stop the loud popping sound that almost sounds like an exhaust leak?

 

the reason your car backfires on deceleration is because your shutter valve may not be functioning properly. during deceleration, the shutter valve cuts the air/fuel mix off to the rear rotor. to prevent engine drag, you have a coasting valve which supplies fresh air to the rear chamber. these two things when working really help cut down on backfiring. its really a good system. your fresh air tube is very vital to the life of the converter. this tube will carry fresh air from the acv to the converter to clean up the exhaust. it will also help to cool the converter. without this tube, you can melt your converter's inards very eaisaly.

 

So which valve is my shutter valve and what should I do?