re. hard start

[Ben Swann]

[Hello campers,
The latest curiosity with the 87 5KTQ is that its not starting when warm.
After checking the usual suspects, vacuum leaks, etc, I pulled the boot on
the metering unit, turned on the ignition and lifted the air plate,
expecting the injectors to fire... to no avail.
The fuel pump wouldn't run till I had bridged the f.p. relay.
Am I missing something, or is the "safety circuit" prohibiting the pump
from
running.. and, ifso, what is the "safety circuit"?
The older K-Jets had a contact on the side of the unit that locked out the
pump until the air flap lifted, but, between the Bently and a dedicated
Bosch manual, I can't identify it on this setup.
What am I missing, and is there a way to hotwire the thing, without leaving
the fuel pump relay bridged all the time?
Thanks in advance
Mark Woodland
P.S> I am in the process of moving, and need to either fix or sell, (or
both) A.S.A.P.]

Mark,

You are on the right track in bridging the fp relay, as the first test is
to run the fuel pump.  You should hear it kick on and run continuously
while the ignition is on.  You can crank the engine over, and fuel pump
should still be running, while the relay is bridged.

If you pull an injector, you should be able to see it spray when you lift
the plate.  That confirmed, then you might want to look elsewhere than fuel

I assume you attempted to pull codes after cranking, and there are none.

Hope this helps.

Ben