vacuum lines discounted, nothing happens?

[tigmaned]

my 86 vette is idleing a little funny and failed emissions at a idle, so i was looking for some thing to be out of place?? trying vacuum lines one at a time i started to notice disconnecting them didn't change how the engine reacted? i disconnected them right on the right back side of the intake and nothing changed. this is not right is it, vacuum is really important to a engine. so any ideas what this is telling me, or i am i nuts??

 

[tigmaned]

PCV system question, last owner put some chrome Edlebrock value covers on, and the right side one has a air breather in it with the tube runninh up to the intake. and the left side has the PCV in it. i was wondering could the air breather be defeeting the PCV system?? i am going to try it and see what happens. i am kind of thinking it just needs the tube going into the value cover and not the breather.

 

[rrubel]

You're saying you've got the tube from the throttle body *AND* a breather? That's a definite no-no on a MAF car - air comes through the MAF, gets diverted to the crankcase by the tube on the TB, then gets metered out by the PCV valve and fed back into the intake on the driver's side. Adding more air to the mix will cause the car to run lean.

Are you sure the chrome thing actually is a breather and not just a place to attach the tube? If there are no holes underneath it then it's not a true breather.

[RICHR]

 

[tigmaned]

Richthanks, after i failed the test i have been looking at every thing, and i will look at it again but i could sware the Edlebrock things is a breather and has wholes under it? and why i started to question it defeating the PCV system on the other side. not sure this is why its idleing funny and cause high hydrocarbons but worth try. by some pictures from my Hayne's manual and GM service manual, i think i am missing some little divert value deals?? i am going to bring the book in to napa and see if they can find them.

 

[tigmaned]

no its not a air breather on the right side value cover, just a chrome deal with the Edlebrock name on it, and it does have the metal tube hooked up to it going to the intake port. other then that still figure this out? i did get a better picture of the vauum lines and i do see something different on the PCV side that i don't have the same way, so i will get it like the drawing and see.