95 SNOB EFI GT-40 stalls out

I just sold my 88 SN 2001 and purchased a 95 Ski Nautique open bow with the EFI GT-40 motor. I am unfamiliar with the EFI system....... the motor runs fine while out of the water at home, but when I'm at the lake the motor does not idle well. It seems to surge up and down and then stall. Also in rough water the boat will cut out at various rpm's, like I'm losing electrical power or the fuel pump is cutting out. At one point the boat would not start until I let it sit for a few minutes.

There is also a distinct whine when driving, like an old v-drive would make.

My 88 SN was bullet proof with absolutely no problems......... I think I made a mistake upgrading to an open bow ( wife and kids pressured me ).

Should I be headed to a boat shop, or can I tackle these issues on my own ?

Thank you

I would look at the idle air control, throttle position sensor, or throttle plate. It sounds like the computer is trying to compensate for a vaccum leak or bad sensor.

todicus wrote: Thank you very much for your input....... I will let you know what I find out once I do as you both have suggested. One question about the 1.23:1 transmission..... my 88 SN did not whine, is that because it was a 1:1 and not a 1.23:1 ratio ? Thanks again, Todd

Yup, thats it. Not sure why the Powerplus 1.23:1 whines, but they all do. I remember when my uncle bought a '90 (we had an '88 at the time)- that whine sure took some getting used to!

no it's not

Found out the problem on my 95 GT-40 EFI. THe wire that has the in-line fuse which goes to to battery was corroded. replaced it and everything works great. Should of checked that first before I replaced all the electrical components I could find through SKIDIM. But at least I know which parts are new and should not be an issue for the future.