1996 350 Mag EFI Stalling after long idle

[C5stein]

I have a 96 Centurion with MerCruiser 350 Tournament Ski engine.
Serial number: 0F609595
It starts right up cold and runs fine. After running up the river 30 or 40 minutes and then anchoring for 30 minutes to an hour, it restarts, but seems to run a bit rougher. Volts are at 13, temp at 160, Oil Pressure 50-60, fuel level fine.

After putting for a while through 5mph zone when you roll into the throttle is starts to stall out like it is starving for fuel. It is hard to start without putting into neutral and revving it. Sometimes it stalls again, after several attempts it restarts and seems to run rough below 2000prm and fine above.

Any ideas where to start trouble shooting?

Thanks,
Mark

 

[danond]

Re: 1996 350 Mag EFI Stalling after long idle

Have a shop plug in and pull the ECU codes. It should be seeing a strange reading from a sensor. At very least it's a good place to start, and the quickest way to finding the issue if a sensor is misreporting.

 

[C5stein]

Re: 1996 350 Mag EFI Stalling after long idle

Thanks for the help.
Will an automotive GM Tech I or Tech II scan a boat for codes. I know a guy that has those.

 

[dvan1901]

Re: 1996 350 Mag EFI Stalling after long idle

When was the last time you changed the fuel filter and fuel water separator?

 

[C5stein]

Re: 1996 350 Mag EFI Stalling after long idle

I changed the water separator/filter last summer. I usually store the boat with a full tank of fuel with stabilizer, but this winter with gas prices soaring, someone stole my gas, they did put the gas cap back, but I guess there could have been some condensation. The thing is, the boat was doing this last year, before I changed the separator/filter. It's just that the problem was less frequent.

 

[dvan1901]

Re: 1996 350 Mag EFI Stalling after long idle

Maybe change it again, and if you can somehow make sure you don't have debris in the tank. Also, not sure, but I wonder if your gas line is getting too hot. Just a thought. May just need a general tune up. Change the plugs lately?

 

[JustJason]

Re: 1996 350 Mag EFI Stalling after long idle

No the GM tools will not work. GM tools read OBD, OBD2, and CAN based systems.
Marine ecms are known as MEFI with a few generations of their own.

Different language.

 

[Nick Welch]

Oil change and transmission specs

 

[GA_Boater]

Oil change and transmission specs

There must be some meaning to this post, but only you know what it means.

But it was a waste of time since the thread is 9 years old.

Closed.