burtonboy

iTrader: (1)

Im pretty sure I have a vacuum leak. That seems to fit all the symptoms. Im hearing a hissing noise coming from the engie and have a surging idle.

I havent't really noticed any problems performance wise, but i wouldnt really know as ive only had the car about a month and its had the leak the whole time. Its still got plenty of pickup , but it is the fastest thing ive ever driven so again i wouldnt know lol.

It sounds like its coming from the front of the intake, not necessarily from the intake but in that general area. The car is a 94 with an ls1 swap from a 98. He said he removed all the smog stuf and the abs is not connected.

how do I find out where the leak is? are there any common areas to check?
any help would be appreciated

RPM WS6

iTrader: (3)

You said it seems to be coming from the front of the motor..... Is the air bellow slipped correctly onto both the throttle body opening and MAF opening, and the clamps properly snug? Is the TB itself fully torqued onto the intake? Also check that the PCV line on the passenger side of the intake is properly seated, as well as the fresh air line on the top passenger side of the TB.

Low N Slow

iTrader: (4)

Check the rubber bellows for holes, pretty common for them to tear.

philetus

Get a can of carb cleaner and spray it around the engine, with the eng. running. If theres a vacuum leak, you'll find it quick.

burtonboy

iTrader: (1)

I read on here where someone said to do that. are you just supposed to spray everywhere until you find the leak? is it ok to spray flamible liquids all over your engine compartment?

MIKE_84

just spray around with a can of B-12 car cleaner, you'll hear your engine change when you get close.

phillyz28

iTrader: (6)

i have a vacuum leak too.. just found mine right after the throttle body... just got my car a few months ago too. whats the best temporary way to fix the leak? its a small hole

RPM WS6

iTrader: (3)

You mean a small hole in the air ducting between the MAF and the Throttle Body? Just replace that peice of ducting. I beleive the part is only about $30-40 from the dealer.

phillyz28

iTrader: (6)

ummm not really sure... its a small rubber tube, maybe about 1/2 inch in diameter and it shoots off to the left then connects to somethin else then that thing goes back toward the firewall

227Hawk

iTrader: (1)

Sounds like PCV hose.
Hawk

RPM WS6

iTrader: (3)

I'd guess that too but he said "goes off to the left".... the PCV system connects to the intake (TB area) on the passenger side (right) and doesn't go to the left until it gets behind the intake. Maybe I just misunderstood...

Only thing on the front left side of the intake is the EVAP line. But that's hard plastic (not rubber).

Probably is a PCV line or the fresh air line on the top of the TB going to the valvecover.....

227Hawk

iTrader: (1)

I'm guessing that he's looking from the front.
Hawk

phillyz28

iTrader: (6)

yeah im lookin at it from the front... also i dont know if this helps but if i have the AC on and i gun the gas, the air turns off

RPM WS6

iTrader: (3)

So is the hole in the rubber line that runs from the top of the throttle body to the passenger side valvecover? Or in the line that runs from the passenger-front side of the intake all the way behind the intake?

You can get replacement PCV system parts either from the dealer or you could patch something together with PCV line and plastic couplers from most autoparts stores.

phillyz28

iTrader: (6)

another thing that might help.... i went to autozone to pull codes b/c the SES light has been on and here is what came back... 6 codes, maybe #3 has somethin to do with it..

1. system too lean bank 1 po171
2. system too lean bank 2 po174
3. EVAP emission control system leak small po442
4. Idle control system RPM high po507
5. system too lean bank 1 po171-PD
6. system too lean bank 2 po174-PD


also here is a pic of where the leak is:


sorry for the crappy pic, its from my cell phone.. the leak is right in the center of the pic. i tried to tape it up (its the refective surface u see) to see if my SES light would go away but obviously i have a lot more going on then just the leak. its isn't the tube that comes out across the top of everything but its the shiny part beneath it. Sorry for my noobieness by the way

01'WS6

Thats your pcv valve. Just get a small piece of hose from your local auto parts store the same size and length that is going from the pcv valve to the intake and a new pcv valve while your there and all your problems should go away.

PS: The pcv valve is the shiny metal contraption inside that hose that you taped up.

phillyz28

iTrader: (6)

there was nothing inside the hose i taped up... it was just hollow rubber but ill stop by the store and check it out. i know its a stretch but do u have any idea what part number or that would be?

phillyz28

iTrader: (6)

how hard would it be to change something like that myself?

phillyz28

iTrader: (6)

ok, got the new valve and some tubing. anyone have any tips before i try to get this thing done?

phillyz28

iTrader: (6)

ok... got the tube changed but im still unsure of how to get the valve replaced