running along the top of each intake there is a tube, runs along the top outboard of the fuel rail...joins at the back of the engine near the firewall at a big valve, where the two sides meet in the middle there is supposed to be some kind of junction on each side. Those are missing on my motor and it sounds like an exhaust leak back there. What the heck are those pipes and what are those unions called?

 

sorry..forgot to mention she's a 1988 v12

 

Air injection tubes.

The left and right sides are joined by a piece of high temp hose, and the check valve should have a hose as well.

Cheers
DD

 

Slgiht memoery fog. I think there should be two hoses, right and left, which joing the right and left sides to a "Tee".

Something like that.

Someone will have a pic (or clearer memory)

Cheers
DD

 

thank you...seemed like EGR or secondary air injection.