Unfortunately the Vanagon ECU is not looking for an oil pressure signal so it
can't be that your oil pressure is zero (whose isn't before you start the
motor?)  Normally when you turn on your key you should hear the fuel pump
turn on and off quickly (only a couple of seconds of running).  If not then
you could suspect the pump, the ignition switch, the relay for the pump, or
the ECU.  Since you have already heard the pump run when you jumpered the
connections at the ECU I would rule out the pump, and the relay.  So now you
have a choice of either the ignition switch or the ECU.  I have a good used
ECU (1.9l) that I would sell for $125 (need core) if you found you needed it.
 Or I could sell you a rebuilt 2.1l ECU for $200 (need core).  Let me know
what you want to do.

PS Prices are in US Dollars!!

Thanks,
Ken Wilford
John 3:16
www.vanagain.com
Phone: (856)-765-1583
Fax: (856)-327-2242