2002 HPDI Intermitant no start- bad wire, sensor???

[Dstarok1]

I have 2002 150 HPDI's. Port motor wouldn't start last time out after running fine. Starter spun flywheel, but motor didn't fire at all. Looked at what I could on the water, it was in neutral, had no alarms, had fuel, oil, etc. Limped in on starboard motor. Trailered it home, pulled cowling and checked wire connections, poked around, didn't see anything obvious. Checked for spark at plug and - motor started. Started several times. A week later and I decided to change the direct inject oil pump as a maintenance item, and tried to start it afterwards and same thing happened. It just spun but didn't even sputter to try to start. Pulled cowling and poked around some wires again, made sure connections were tight, etc. Tried to start again and it fired right up. I need to find that "smoking gun" so I can trust this motor! Any guidance would be greatly appreciated! By the way, it's starting still, YDS doesn't show anything wrong of course, I should have connected it when it wouldn't start maybe?
Thanks for any help!

[rodbolt17]

no single sensor can cause a no start when cranking.
however the pulser coils provide the main signal to inject fuel and spark.
the main relay provides 12v to the ign coils,injector driver and the medium pressure pump.
most of this can be monitored with YDS.

[Dstarok1]

So you think the main relay could be the having an intermittant fault? Would only show on yds when fault is active. I'll take a look at it. Thanks.

[Dstarok1]

Thanks rod you steered me in the right direction, the injector relay case is chipped on the top so hopefully that was causing the relay to act up, surprised that it's intermittent though.

[99yam40]

making it where all can see it real good

[Dstarok1]

I switched the relay to the other motor and the intermittent problem followed it. Installed new relay and hopefully won't have THAT problem anymore.
Thanks again.