Emulate injectors - how?

You can get 4-pole double-throw relays, can't remember where I seen them
but I definitely came across them as I was going to use it as part of a
car-phone kit with the two front speakers (two wires in each being
switched hence the 4-pole required). Never seen an 8-pole, but it would
be pretty huge packaging wise - the 4PDT has 14 pins!

Paul.

 

Depends on the vehicle in question. Most fuel pumps run continuously
and pressure regulation is done by releasing fuel from the rail back to
the fuel tank. Some late model vehicles simply moved this regulation
fuction back to the fuel pump itself, but it still runs continuously. I
dont' know about your specific vehicle, but on the ones I'm familiar
with, the only reason that the fuel pump shuts off a few seconds after
turning on the key is because the auto shut-down system isn't detecting
ignition pulses and kills the fuel pump. As soon as you start cranking
the engine, the fuel pump comes back on and (on these vehicles) STAYS on.[/QUOTE]
You could be right, but it's done 50k+ miles on LPG with typically the
petrol pump used once a day just to prime the system to start on petrol
to avoid a lot of cranking to get the gas through if its stood for a
while. I actually put the switch back to gas before actually starting
the engine.