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Fuel Pump operation on E12

>> About hard starting due to lack of fuel pressure when the engine is cranked because the fuel pump
doesn't begin to function until the engine begins to crank...

Eric Tangen  wrote: 

> The pump operates: 1. while the starter is cranking & 2. when the flap inside the air flow meter
moves >off the fully closed position (there is a reed switch under the plastic cap on the AFM that
senses this). 

>You can turn the fuel pump on by putting the ignition key to the 'on' position and lodging the air
flow >meter door open, all without having the engine run.

Thanks Eric...
  I have an 86 VW Scirocco which had a fuel pump relay that ran the fuel pump for one second when
the key was on 'ON' position/cranking position (by the time you got to the turning the engine, the
pressue in the fuel system  was already built.  When that relay went out, I got an aftermarket one
and this one only runs the fuel pump when the starter is cranking or engine is running (no priming).
The car seems to take more cranks to start now...

One suggestion earlier (from Douglas Wyman) was to add a check valve before the fuel pump, because
the one built in the pump may be leaking, to prevent losing presure.  Apparently this works well...

My question:  Is is possible to get a fuel pump relay (or other solution) for the E12 that will
prime the fuel lines (run the pump for a second) so the system is already pressurized when the
engine begins to crank?

Thanks, Sergio
  juans@domain.elided
  '79 528i 180k...