vacuum leak. NEED HELP

[awesomeguy6154]

i've got a 96 gt thats pretty much stock except for a cat-back, o/r x-pipe, and CAI. Right now it idles like SHIIT. I'm almost positive it's a vacuum leak, but I have no idea where to look for one in the engine bay or how to tell if there even is a leak. Help me out. Pics of the engine bay would be nice too if you can.

 

[bobtsgt]

you can take a can of carb cleaner and lightly spray over all the vacuum hoses and fittings and hear for the idle to raise up. Also check your CAI at the couplers and where there PCV attaches. Check all the hoses for dry rot and for cracking. It may also be a idle air control motor problem too. May be dirty or acting up.

 

[awesomeguy6154]

where exactly are the vacuum hoses in the engine bay? are they the ones coming out of the intake tube? Im kind of a noob with late models.

Old cars are soooo much easier

 

[bobtsgt]

anything coming out of the intake plenum is a vacuum source

 

[nyuk98gt]

awesomeguy6154:

There's the evaporative canister and hoses all tucked in the passenger side wheel well (behind the plastic shield). Most of the vac lines are easy to locate, starting from the main source hose behind the upper plenum and on the upper plenum. Check the EGR plumbing, too, as it may have some wear and tear issues. You can use a plumber's bottle of propane and a hose rather than carb cleaner -- it's a little less messy. Vac leak finding should be done in the driveway (NOT the garage).

Are any codes showing up? Usually a vac leak will cause a lean condition or something to cause the CEL to pop on.

HTH,

Chris

 

[awesomeguy6154]

The CEL comes on and off intermittently. I've tried to get a code from it before but nothing ever shows up. It doesn't seem to run any differently when the light is on though. Also, sometimes when I punch the loud pedal the motor stumbles for a little while and then picks itself back up. Could this be related to a vac leak?

 

[joelbegt]

Well a stuck open EGR valve can cause crappy idle and a stubble on acceleration too. but I'd check for a vac leak first if i were you, and then go from there.