4.3gxi bad temp sensor?

happychapboater said:

Could it be a fuel issue? If I have the bad motor running and start the good one, it’ll cause the bad one to cut off.

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Anything is possible but both idling shouldn't cause one to die. If electrical connections are bad, maybe

Alternator outputs the same when running, should be around 14V+

alldodge said:

Anything is possible but both idling shouldn't cause one to die. If electrical connections are bad, maybe

Alternator outputs the same when running, should be around 14V+

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When the bad motor was running and I had given it throttle to stay running and I turn the other motor on, the bad engine would shut down like it was cut off from fuel.

Sure sounds like an electrical problem

alldodge said:

Sure sounds like an electrical problem

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Now I tried starting it this morning and it won’t turn over. I hear a click when I turn the ignition, removed the starter motor and solenoid and that worked when I tested it. I put a brand new battery on that engine a few days ago and it’s been on shore power this entire time.

Look real, I mean really, really close at your battery cables.

Try to bend the cab;e ends enough to see under the insulation jacket on both Pos and Neg ends. Wouldn't be the first time that a cable looks great but under the jacket it's corroded

A little update: Yesterday I went back to the boat, and it started up right away so not sure what the no start issue was. It's on a brand new battery so maybe a charging issue? Still stalling though. I checked the ecm grounds. The sensor ground was giving a high resistance reading on the meter. I back probed the sensor ground and connected directly to the battery negative and it idled nice and smooth. I tried tracing where the wires went for the ground to clean up or look at more but it looked like it went behind the motor and that is going to be a challenge to get to, unless it runs somewhere else I wasn't seeing. Any advice on that would be helpful.

Also, after the engine stalled there was a noise that sounded like wind coming from the port exhaust anti-siphon valve through the flame arrestor and a slight gas smell that dissipated.

Motor side grounds are on a bolt at back of the motor