Warning: Huge image below.
Hey guys, I've got a problem that I need help with. My 1991 Audi 80 quattro has been running VERY badly for the past week. It essentially cannot rev beyond about 4,300 RPM or so anymore before running completely out of power and just chugging and wheezing. From 0-4,300 RPM, it's very very low on power. We're talking a 0-60 time in the 20-something seconds range. The car is so low on power, I'm almost unable to merge onto the highway. There's also excess engine noise when under heavy throttle loads and there's a sound coming from the injector area that sounds like a blend of hissing and clicking, which increases with engine load and RPM's. I've also got an uneven idle.
I've already swapped the plugs (went from Bosch to NGK), distributor cap, and distributor rotor. The wires are fine. I was checking the vacuum lines and looking for leaks when I noticed something odd. In the picture below, which was taken about a year ago, I've highlighted a blue rubber cover/nipple, which attaches to the end of a small pipe which travels down to what looks to be the side of the block or the crank-case, though I'm not sure as it's difficult to see.
The blue nipple in the picture is intact, but when I look under my hood today, I noticed that it has pretty much been obliterated and has dried to the point that it has broken in half and the end of the tube is blowing VERY, VERY hot gas out into the open air. Upon partially plugging up the end of the tube, the injector-area noise goes away and the idle smooths out.
So my question is: what is this rubber tube end/nipple called and where can I buy a new one ASAP? This is my only vehicle and if the engine starts running much worse I'm not going to be able to get to work and back.