i have a 03 which has the 3.2 v6 so im not sure if its the same as the 2.8 and/or the 3.6 but anyways.

a little back story is prolly in order.

i have been having rough idle which is made worse when i put on the a/c so i took it to gm and they did a once over. since it isnt throwing any codes he said it is hard to detect but he said the throttle body was dirty and cleaned it and added some cleaner stuff to the gas tank, but it still isnt running any better.

i read on some forums that it could be dirty contacts from the throttle body sensor so i as i went to take a look i remembered a post i read about a vacuum line being disconnected from under the throttle body and once put back on it ran fine, so i checked, and hot dog my line is all cracked and ripped up. this line is about a pencil thick and the only rubber part is the elbow that attaches to the throttle body, the rest is plastic and runs under the plenum(sp?) so i have no idea where it goes or even if it truly is a vacuum line.

so my question what is the line and could it be causing a rough idle? and of course if it isnt, what else could it be?

thanks in advanced.