Power Loss/ Struggle, 2007 250 ProXS

[stratos976]

2007 ProXS
s/n: 1B498795

Last time out when getting on plane the boat really struggled, felt like a carbed engine that gets "loaded" up on a cylinder or two. It also seemed to struggle to get to full rpm although I didn't push it thinking there may be an issue. No audible alarms or messages on smartcraft tach & speedo

At home I pulled the plugs to check for anything abnormal, all the plus were replaced in January. They were all similar except #4 (center port side) was wet compared to the others, not sopping but clearly wet compared to the other 5 plugs which looked dry.

I swapped coils with #2 to see if the problem follows the coil, I will take it tomorrow to see if that's the case. Could that possibly be it?

Possible injector problem?

It has also struggled to consistently get to temp the last couple trips. could this cause an issue like this? I'll pull the stats and check them before I test it tomorrow.


I'm working to get it in for freeze frame readouts next week.

[Jtreed99]

Running cold can absolutely foul a plug and will present as the symptoms you mention. Bad coil will also result in wet plug and the same symptoms.

[EuropeanAM]

Start with the KNOWN problem- failure to reach operating temp.

[stratos976]

I cleaned the stats and checked, stbd side had a little grass in it, both actually opened in full hot faucet water which is less than 120. I reinstalled and on the hose the engine only reached ~93*, so I installed new stats, now I’ve got 130*.

Ran the boat and still had the miss, swapped coils from cylinder 4(wet plug)and 2, ran boat and still had miss which was expected, the wetness followed the coil, so I replaced coil.

this resolved the low power/miss and low temp issues.

Thanks for the help.

[EuropeanAM]

Good job, Andy!