Intermittent stalling, RPM drop, misfiring...oh boy

So it wasn't the OVP.  I replaced that with a brand new unit and the problem persists.  To refresh, here's what has been plaguing my 300e. 

Very intermittently my car loses RPMs and stalls, but ONLY under load.  This first happened once in a parking lot after warming up, then again in the driveway.  Not too long afterwards, I parked the 300e for a bit since I didn't have a place for it, and it now does it about 40% of starts.  It is fine when cold, but after it warms up, the idle becomes rougher and as soon as you step on the gas a bit (still in park) it misfires and shakes badly up until about 2500 RPMs.  However, shift it into drive or reverse and it does the same misfiring but the RPMs drop until it stalls.  I thought it was the OVP since that is a very common replacement item, but no luck.  Also, during this time I found that my EHA valve (stands for electrohydraulic actuator) began to leak massively.  Again there was a glimmer of hope, but even after replacing it with a known good part, the problem persists.  Actually, I might as well just list all the stuff I've checked

- replaced ovp with new unit
- replaced cap and rotor, just inspected them again today to see if there was anything wacky there...cap had some usual corrosion on contact points but nothing out of the ordinary
- replaced wires, checked again for arcing today and nothing
- replaced EHA (was leaking wildly, had to be done anyways)
- checked engine temp sensor, appears to be fine
- checked the flywheel crank sensor (which goes to EZL), came out to 880 ohms, which is well within spec
- replaced O2 sensor
- fuel pump is always on during this so that rules out FPR
- replaced spark plugs (proper style - ordered from here)
- checked vacuum connections, seems fine
- duty cycle (checked via X11 diagnostic port) remained within 47-51%, which is very good--Lambda tower does not need adjustment.

Really not sure where I am heading from here.  I think I am going to replace all of the vacuum lines that I can find and hopefully fix any leak that might exist.  Stay tuned....