While I'm waiting for parts I decided to do a more thorough check for vacuum leaks. I pulled the intake from the throttle body and capped the TB with a rubber glove. Then I removed the PCV hose from the intake and capped the intake barb. I pulled the hose from the PCV valve and capped it. So now the intake is completely separated from the crankcase / lifter valley.
I hooked the smoke machine up to the TB barb and let it fill. I was able to build enough pressure to fill up the glove and can't find any leaks.
I wiggled all the injectors to check the o rings and really gave everything a good look over. I pulled the line from the oil fill tube and there's no smoke in the crankcase. I would think if a lower intake manifold gasket was leaking it would be leaking smoke into the lifter valley and visible in the oil filler tube.
I also did a similar check of my PCV / catch can set up by capping one end and smoking it. No leaks.
Because some of the vacuum paths have check valves, pressurizing with smoke won't reach them. So....
I pulled the check valve out of the master cylinder. Still was holding vacuum but smoked the master cylinder anyway. No leak.
I pulled the vacuum line from the check valve to the cruise control vacuum can and smoked it. No leaks from the cruise control lines or vacuum canister.
I pulled the climate control vacuum lines from the check valve on the firewall and smoked the vacuum ball in fender well and also the line going into the car for the blend doors and control. No smoke in the car.
I reassembled everything and then smoked the intake from engine through Vortech and oil seperator to MAF. No unmetered air leaks.
Just to rule out the catch can, I bypassed it and fired it up. There's no change in the low slope.
I'm not seeing how I could have a vacuum leak after this. If I'm missing something lemme know.