Fuel Pump? Relay? Inconsistent Starting

[MISFIT 1]

check your fuel pump ground. I had ground issues as well as a bad ignition switch

[spdbrake]

You didn't mention what type/brand EFI you installed.

You mentioned you normally hear the fuel pump humm a few seconds after key-on which would describe a returnless system. Typically relies on a pressure switch.
Do you have pressure gauge on the fuel rail?

Try cracking a line at the fuel rail to see if you already have pressure there. (have a rag under the fitting be ready to grab the fitting with the rag to catch any spray.)

Sometimes an intank pump can hi-side and produce too much fuel and flood your plugs. You might pull one to check.

A set of piercing probes are handy for checking power and ground in active circuits. https://www.amazon.com/Goupchn-Insul...316302&sr=8-11

[CHANMADD]

I have an oil pressure cutout switch on my car.. The engine will crank until the oil pressure comes up and then the switch will set the fuel pump relay. The switch should be located at the oil pressure takeoff point on the block. So when there is no fuel pressure it will not start....until you've cranked the oil pressure up. Also if you run out of oil the motor will stop.. If you crash and stall the fuel pump will stop as soon as the oil pressure drops.

[thedome]

Thanks guys for all the great info. I have some more investigation to do based on your suggestions. I have a Fitech EFI system and no return. I do not have a fuel pressure gauge inline.

[eschaider]

Originally Posted by thedome

Thanks guys for all the great info. I have some more investigation to do based on your suggestions. I have a Fitech EFI system and no return. I do not have a fuel pressure gauge inline.

Is your system then a returnless system?