PunchyTurtle
Cadet
- Joined
- Aug 4, 2023
- Messages
- 6
This is a 2005 50HP Mercury EFI. It's been having weird fuel delivery issues that have been intermittent and displaying a wide variety of symptoms, making it really confusing and hard to diag.
It started with low idle while warming up, to excess fuel spilling out of the VST at idle (twice), and loss of fuel pressure after shutoff causing hard starting (continuing issue), and now this surging situation has started. It almost seems like a cold cylinder.
It will persist as long as I've let it. But, when I open up the throttle, it will stutter and be doing the same repetitive surging loss of power thing for maybe 1.5 seconds, after which it will seemingly work itself out and run smoothly and entirely normally. It then runs perfectly normally until I shut it off and allow it maybe 10 seconds before starting back up again. It will have lost most of the fuel pressure at that point, and the surging thing does not happen every time.
I attached a video of the surging thing it's doing.
It started with low idle while warming up, to excess fuel spilling out of the VST at idle (twice), and loss of fuel pressure after shutoff causing hard starting (continuing issue), and now this surging situation has started. It almost seems like a cold cylinder.
It will persist as long as I've let it. But, when I open up the throttle, it will stutter and be doing the same repetitive surging loss of power thing for maybe 1.5 seconds, after which it will seemingly work itself out and run smoothly and entirely normally. It then runs perfectly normally until I shut it off and allow it maybe 10 seconds before starting back up again. It will have lost most of the fuel pressure at that point, and the surging thing does not happen every time.
I attached a video of the surging thing it's doing.