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Help - Engine won't start - ECM

JimC1965

New member
I have a1998 Shamrock with a Seamax/PCM GM 5.7 Liter engine with EFI/TBI. The boat willnot start unless I pour fuel directly into the intake. Prior to it not startingwe were idling or running at low speed in the bay when the engine stalled andthen restarted immediately on 3 occasions. On 1 occasion the engine did notrestart immediately, but restarted after several minutes. The next time I tookthe boat out I had no issues at all and I could not get it to replicate theproblem. When I went to take the boat out on Saturday the engine would notstart. I am getting no power to both the electric fuel pump and the fuelcontrol cell. All fuses check OK. The relays are firing. I am thinking the ECMhas failed but not sure and with the cost of a new ECM I want to be sure orconsider other options. Any ideas or help would be appreciated.

 
What do you mean "...relays are firing."??

does the fuel pump run briefly when the key is turned ON ??

Do you have spark?
 
What do you mean "...relays are firing."??

does the fuel pump run briefly when the key is turned ON ??

Do you have spark?

The relays are working.
The fuel pump doesn't run at all. No power to fuel pump or FCC a anytime.
We have spark. Engine runs for a bit when throttle body is primed.
 
Assuming you have verified the relay passes current without excessive voltage drop, have you checked for voltage at the fuel pump connector?

You could also try jumping the fuel pump to a (fused) source, directly, to see if it runs.

I'm thinking a 1998 should have the MEFI-3 controller which should turn on the fuel pump for a couple seconds when the ignition key is rotated to the RUN position.
 
Thank you to everyone for your input. I located a corroded butt connection which caused the wire to the fuel pump and FCC to break.
 
glad your resolved the issue.....and now you know why the better crimp connections are sealed with heat shrink tubing!!

Happy motorin'
 
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