Thanks Arthur.

EGR valve does hold vacuum when pumped down; engine vac @ idle is 20" (as read from the hose that feeds to SOV). Is that high enough?

I'm pretty sure the vent on the SOV is okay because I pull vac before the SOV and activate by applying 12v, the EGR valve clicks shut when removing the 12v.

Where is the pressure sensor?

as ever
Paul