Toxiclemonade

I was hot-******* my car last night, enjoying the weather, and when I got home I noticed a hissing sound coming from the back of the intake manifold. It sounds like a sucking/vacuum leak. Is there a hose or something on the back side of the car that could have come off? What about an intake gasket? Any help would be appreciated. Thanks.

Car is a 2000 c5

redrckt97

most likely is the little vacuum line that runs the hvac system vents came loose. See if air comes out all of your vents at the same time -thats what hapeens when the little line comes off -- its a hard brown plastic line that runs from an elbow on the back of the manifold into the ribbed black wire loom down behind the battery. With some effort, you can get your fingers behind the manifold and slip the line back in place. Do a search on here - there are a couple of good threads on it with pics.

lucky131969

Yes, the vacuum for the A/C and power brakes are behind the manifold. The MAP sensor is there as well.

Toxiclemonade

Thanks for the quick replies. I tried a search but am having trouble finding any decent threads. Any links? The car seems to be running fine, no codes and no performance issues. Just really loud.

lucky131969

Did you follow suggestion from redrckt97 about trying the A/C modes? Since the engine is running fine, that suggests that it is not the MAP. Again, it's probably the small vacuum line.

Check out the thread below.....starting with post #2:

http://forums.corvetteforum.com/c5-t...y-vectorz.html

dougbfresh

Bet your HVAC isn't working quite right!

Toxiclemonade

I took the belt off the ac a while ago. The blower is locked up...

ColeTrain'sC5

yeah mine's doing this as well. Need to get out and fix it

ColeTrain'sC5

Haha i actually felt ambitious tonight so i ran out to the garage and started digging behind the intake manifold and found my line and sure as hell it was popped off. Snapped it back on and the HVAC works perfect now If you still have your A.I.R. lines back there you may have a hard time. I had to take off my EGR lines to get my hands back there because i have big hands so if you have AIR lines it could be real tough.