Ok, this is good stuff. I am guessing since my engine is 4.8, but still N62 this would also apply.

Seems like there is a lot of tubing there that could be leaking. I am going to check this out tonight.

So let me get this straight.
So if I disconnect the hoses at number 5 or at both number 4s, I should get air coming from the blower, but then I should also not get exhaust from same hoses/valves telling me if the check valves are functioning.

I think I got it. I just hope I can get to that pump easy enough without removing the entire intake.

Will this throw a check engine code? If yes, I need to go get my scanner back from my friend before doing this.

On a second note, can I test those check valves off the car. I have an air compressor I can use to blow through it. I am just curious how much that valve can handle. I am guessing it is not much PSI going through there.

Thank ripp.