Yet another surging idle

[dpmit94]

I've tried searching for a similar issue and haven't seen anything that helped.
My idle has been fluctuating between ~400-1000rpm. Just yesterday I replaced the CTS, and just today the Fuel Pressure Regulator to no avail. I suspect a vacuum leak somewhere.

The reason I'm still confused: When I pull the vacuum line from the intake manifold to the FPR, the idle smooths out and it's perfect; how it should be. Runs and drives well with quick throttle response.



Pulling this line should create a massive vacuum leak, right? Why would it solve my problem pulling this vacuum line off?

[flyboyx]

look at your intake gasket. get some carburetor cleaner and spray it around your manifold. also, take off the icv and spray the hell out of it. it could be sticky. have you taken off your intake boot to see if there are any cracks in it?

[dpmit94]

look at your intake gasket. get some carburetor cleaner and spray it around your manifold. also, take off the icv and spray the hell out of it. it could be sticky. have you taken off your intake boot to see if there are any cracks in it?

I have not done that yet. You're talking the rubber boot behind the AFM right? Also the intake gasket as in where it meets the head?