MicroSquirt.com read only forum (Jan.15,2018)

I have a microsquirt v3 running b&g 3.830 firmware controlling a 1981 goldwing motorcycle, fuel only so far.
Would like to set a priming pulse for easier starting, but I have the injector power controlled by the fuel pump relay. This means that the priming pulse has to happen before the fuel pump turns off, or there's no power for the priming pulse.
Thought about extending the 2 sec pump timeout in the 2.891 code, but noticed a line that appears to say that the normal pump timeout is already being extended by the priming pulse delay:

pump_delay = 2 + inpram.prime_delay; // sec

Is this in fact what's going on here and in the 3.830 code? Guess I could just time it myself, but wondering what happens after an engine stall also.
Thanks for any info!

The purpose of prime_delay is to let the pump prime for people who have bad check valves. So the ecu delays prime_delay seconds to allow the pump to prime, then squirts the prime pulse. The code you are referring to is just to keep the ecu from turning off the pump before it has primed.

Assuming you have a good check valve, leave the priming delay at 0. As soon as you turn the key on you will get your prime squirt with or without the fuel pump being on, just from residual gas in the lines. But if the pump and injectors are wired together, then the pump will stay on for 2 seconds without cranking. This is more than enough time to get a prime pulse provided there is fuel ready (good check valve). If not, and there isn't enough residual fuel in the lines, then set a priming delay. It won't squirt the prime pulse until priming delay seconds, and it won't turn off the pump until 2 + priming delay seconds.

Thanks for explaining, its great to have a code author accessible like this!