I just took my 2020 sx xc in for its first dealer tune up since purchasing. I was a little late at 117 hours, but it ran great for the first 110. The last few weeks its been bogging down, sometimes hard to start, and sometimes it'll just die when i slow down to an idle. The dealer supposedly did a 24 point inspection, adjusted valves, changed fluids, etc... its just as rough as before i took it in. I should note that its not all the time... sometimes it does it sometimes it doesn't. Today i drove about a 1/2 mile and it bogged down sIightly a couple times but ran great otherwise...until i got to the hill by my house and at one point i didnt think it was going to make it up it. I threw it in 4x4 and it carried on. Literally as i pulled in the barn it died. I started it right back up and drove the 3 more feet i needed to park it. I feel like its fuel, but I always run ethanol free only, except one time at about 50 hours i put some old fuel in it out of desperation... but it's ran great a lot since then and just got real bad recently. Should i clean the tank and replace the lines? Could it be the battery? I need help!

 

Take it back to your dealer that just did the 24 point inspection and explain to them what is happening.
A vacuum line, something getting bumped and got loose? If the dealer is worth their salt, should be a no charge call back. Did the fuel filter get changed out if that is covered under the 24 pt inspection. I have had a bad float once that caused similar issues. Good luck