bad Gass Maybe?

[Brownmaniac]

need some help from some of you experts.
just purchased a 2016 bass cat with a 250 pro XS. It's my first fuel injected motor. Ran it for the first time last week and it seemed to run flawlessly. Headed out on the lake yesterday wound her out to around 5600 rpms and noticed a HARD, intermittent skip or (miss). The timing of the skip was random. It also skipped at idle. There was about a half tank of fuel in one side that was in it when I bought it. Guy said he ran the cheapest gas with ethanol and that it had sat for two and a half months. I topped it off with premium non- ethanol and headed to the lake. i switched tanks and it seem to do better but I did feel it miss a couple of more times at idle. There was maybe a little less than a quarter of a tank in that one when purchased. Of course I filled it up too.
Any suggestions before I take it to the shop and have to wait for probably a month to get it back? my buddy thinks it's one of the coils.

Thanks!

[Bob G.]

Start with the basics like new properly gapped spark plugs and inspect or replace the spark plug wires. A spark plug wire can start corroding internally at the boot long before you will see it. The fuel in the tanks when you bought it may be questionable too. Read these:

http://www.bbcboards.net/showthread.php?t=22490

http://www.bbcboards.net/showthread.php?t=20401

http://www.bbcboards.net/showthread.php?t=575860

[hstechfl]

Check the 2nd link Bob just posted. Looks like you should be running 87 octane. Not sure if this is your problem, but good place to start.

[EuropeanAM]

Please see the Announcements at the top of the Forum, and provide the REQUIRED info when posting. Thanks!

[Brownmaniac]

Please see the Announcements at the top of the Forum, and provide the REQUIRED info when posting. Thanks!

sorry.... S# 2B124967

[EuropeanAM]

I would make a visual inspection of the Spark Plug Wires & Spark Plugs... and verify ALL of the BASICS (Compression, Spark, Fuel Quality/Delivery/Air-Fuel Pressures).

[letsgocanes]

Find an engine mounted fuel line, disconnect and catch the fuel that comes out when you turn the engine over? Just make sure your kill switch is out. I'd ask permission to do this first though. If it's milky, it's water.