Under hard acceleration or going up a hill at 45 I get wild vents. I replaced the check valves with flow to the intake (blow on it and it stops). The only think I didn't do was smoke test it.

My vacuum gauge which it right as the vacuum booster exits the center head. It got to about 3-4 hg at this time. Im out of ideas here.

 

Did you check the vacuum tee under the battery tray at the vacuum canister? Know to deteriorate due to battery acid exposure.

 

Those are classic symptoms of low vacuum pressure. You have a rotten hose or cracked line somewhere. How many miles on the engine. If you have a BUNCH of miles, the engine could be worn. If every single line is checked and found to be good, you can add a vacuum reservoir. These are those black ***** you see under the hood of a lot of Mopars in the 80's. They have a single vacuum line going to them. They hold a little extra vacuum pressure to keep the vents from moving so much.

 

Every line was replaced that I could see. At idle it makes 28 in hg of vacuum

 

Yeah its good. The only two things that are affected when it gets low is cruise and vents

 

Think I would check the check valves, and maybe install another vacuum reservoir.

 

Just found out im burning oil

 

Plenum bad?

 

Nope was replaced with an aluminum one and new Fel-Pro gasket I did a compression check here is what I got.
#1: 120
#2: 110
#3: 130
#4: 110
#5: 125
#6: 90 100 wet
#7: 125
#8 130

 

Don’t forget to check the control head, yes they go bad, and they can get crap sucked into them from actuators that are going bad but don’t leak

pull the control head, find the port that gets vacum from the engine and blow .......slight......air pressure backwards into it, while doing that, turn the mode **** from one setting to another, you may get lucky and blow some stuff out of it. Now ya gotta find the bad hose or actuator

its worth a shot