undocumented vats bypass?

[Shannen Durphey]

little story.  Local Ford dealership had 89ish camaro which
wouldn't start.  Found a starter relay, bypassed it, starter
would crank.  But no fuel available.  (mis)diagnosed faulty
ecm, so...R&R.  Vehicle now starts& runs, but SES light
flashes, idles poorly, no power.  Nother mechanic asks "did
you put the prom in?"  "Prom?!?" So Ace heads off and
installs the prom, without shutting the engine off, and SES
light goes out, car runs great, scantool communicates ok. 
All is well until restart is attempted, then back to square
one, no fuel.

To make a long story short, VATS wiring to ignition cylinder
was faulty, ecm wouldn't enable fuel/crank.  With prom out,
car starts&runs on backup fuel.  Install prom after car is
started, ecm uses main fuel/spark maps.  Whoda thunk it.

Shannen