2008 Ultra250 random missing

[pls4541]

Hey all, here's a recent issue with a 2008 Kawasaki Ultra 250 that has the guys at the shop still scratching their heads...
First, the machine was purchased used in March, pristine condition, never in salt, with approx 130 hours. The machine has run flawless all summer on a fresh water lake and routinely gassed up at the local marina with 93 octane NO ethanol fuel. I purchase this same fuel routinely for my other ski's at this marina and have experienced no difficulties.
Last week machine was used to pull a wakeboarder for maybe an hour or so. Afterward, while running solo across the lake the machine seemed to loose power, like a cylinder dropped out, then pick back up, then loose power again, and so on. This was intermittent, both while at idle and while underway. No codes were displayed, no warning lights appeared.
Towed machine home, loaded it up, and ordered a new set of plugs (factory EXPENSIVE plugs) and replaced. Launched machine a few days later and same symptoms present as we cranked it to movie off the trailer with cold engine. Loaded it up and took it to the shop.
At shop, compression ck performed, all cylinders 120+ psi cold, fuel pressure checks good, shop diagnostic computer was plugged up and revealed a "1501", nothing else, but seems we can't determine what "1501" code means...., Issue remains, feels like cylinder dropping out.
Shop indicated they will pull pump just to see if something there is out of order....
This is not a factory shop, but a highly reputable group who has done impressive work for years. Their computer diagnostics is not a "factory" unit, wonder if the dealer may have something better. Any help is appreciated as it's presently a 3 week wait at the dealer shop. Thanks

[Chris288]

plug wires going bad, high resistance ?????

[pls4541]

wires might be worth a check, they look good but who knows...still searching for the definition of "1501" diagnostic code.

[mobiletechguy]

wires might be worth a check, they look good but who knows...still searching for the definition of "1501" diagnostic code.

Ill check them wires first thing Friday morning before I leave for gaston

[nicjak]

sounds like you may have another bad plug, could have a manifold waterleak of which is common. use the cheaper alternative plug and put another set in or swap one out with a good one until the problem is fixed. have you also checked the air intake horn hasnt dislodged? this only effects it at the higher wot running end though. last to check would be measure fuel output at 3sec prime just to see how clean your fuel has been.

[Rescue1]

Is the Belt tight and in good shape for the Supercharger?

[pls4541]

Plug wires #1 $ #4.....$650

[Gsmith88]

What?

[Gsmith88]

That's weird , my #1 and #4 wires went bad on my 310 as well.

[sirbreaksalot]

Plug wires #1 $ #4.....$650

some one is ripping you crazy

they are only $60 each genuine !!!!!!!!!!!!!!!!