fbird95

I know i have a vacumn leak somewhere, Where should i check first for leaks/ bad connections?

GreyStripedZ

ttt

need to know too

ChickenScreamer94

I have ***heard*** you can use windex and spray it on the various vacuum fitting/lines to see if that area is leaking. If your idle goes lower you found your leak. BTW, have you checked the intake elbow for tears?

Fatdog

Might check those little hoses that run along side the pass side of the intake manifold.Those little buggers crappy.My02

slopokrodrigez

First, how do you know you have a leak? Are the IAC counts low?

One way to find them is to get the exhaust as quiet as you can. Putting long hoses over the tail pipes works well. Then you can listen for leaks around the engine. The liquid thing works somewhat but if you can squirt it, you would have heard it anyway. Isolating parts of the system helps in limiting the search to sections. For example pull the hose off the vac check valve and plug the line at the check valve. This will remove the entire HVAC vac system from the engine bay. This will eliminate the lines in the dash board as being the cause or not. Don't forget the hose next to the fuel lines that takes vacuum back to the vapor canister. Remove it and plug the source. This gets rid of several feet of vac lines as the source of the leak while you look else where.

Right now I'm trying to get to a non functioning bi-level valve and so far it aint fun. I hate dashboard problems.

Good luck to you.

GreyStripedZ

well i think i have a leak becouse my car is running really crappy..and now my air filter sounds like a freakin vacumn cleaner it so damn load...

fbird95

I was told i have a leak because when i have the a/c on and i stomp on it, the air stops coming out of the top vents. I checked all the lines as Shoebox told me to, and i found the one going into the reserve tank coming loose. Now i get about 5 seconds or so of air through the the top vents when i stomp it, then it reverts to the bottom vents. He said there is most likely a leak because the volume of air is not supposed to change, nor is where the air comes from, its just supposed to blow hot air.

Is it possible that the reserve tank runs out of air after a few seconds, or am i still looking for a leak?


thanks for the replies

Silver

Durrr.. I think that's just the a/c clicking off? I'd verify that you actually had a problem before you started looking for vacuum leaks. My car does that exact same thing and I've never suspected a vacuum leak. I reckon I could be wrong, but I always thought this was normal.

Can't believe no one has suggested the ol' starter fluid method. Just don't blow yourself up.

MentalCaseOne

Talk about leaks.... what would be the acceptable vacum level on a stock z28 at idle??

18inches?? less?? more??


Also I did this once before/// I purchased about 4 feet of fuel line hose at the autoparts store and all I did was put one end up to my ear and the other end on suspicious places... since you will have the engine on... make sure to stay oway from hot or moving parts..

by the way a long hose is best since your head will be placed away from the Hot and noisy engine.... it all depends on how long arms you have (grin)

Marvin

fbird95

Silver, I should really take your advice, and stop inventing problems. It works Fine and i should just not even worry about it, Its just a bad habit i have. That, a hot temper and a short fuse can make for some problems.

Silver

LOL dude you aren't telling me anything. I'm the exact same way!

slopokrodrigez

Hey Fbird, that was a hole discussion on the loos of vacuum. Well it turns out that we all loose vacuum when we stomp on it and the default condition for the HVAC is for the Defrost/floor to be in it's center position. You need to pull the line off the vacuum check valve to see if it pulls in air after the car has been off for a while. If you hear a big rush of air, no problem. If not you got a leak.

fbird95

If i do what you described there is no rush of air. I know i have a leak somewhere, i just cant find it. My friends 94' camaro doesn't have the loss of air flow pressure when he stomps it, so i just wondered.

I'm not gonna worry about it. I rarely use the A/C anyway, i just like everything in order, and right now the sagging headliner is really irritating me. I may recover it tomarrow, because i dont like the prices i see for new ones.