2018 Honda Civic — fuel trims are positive at idle and improve with RPM

Ask what changed right before it started. Two 2018 Honda Civics can feel identical and have different causes, so measure before you copy someone else's repair. That's the branch I'd chase this week. This is from a 2018 Honda Civic in Miami. Learned this the expensive way on a previous car. Parking it somewhere I can hear it better next time.

Log the conditions before you spend. Loaded-suspension checks on the 2018 Honda Civic catch play that a wheels-hanging inspection misses. You'll know quickly if you're on the wrong tree. On “fuel trims are positive at idle and,” that was the fork that mattered for me. Verbal 'we'll take care of it' is not a plan. Climate here is different, so treat that as a local data point. This is the version I'd tell a friend.

OP update: scanned the 2018 Honda Civic again and still only have the one pending code, no new lights. Heat soak after errands is the other window.

OP update: scanned the 2018 Honda Civic again and still only have the one pending code, no new lights. Video is ugly but it shows the hesitation.

I wouldn't throw parts yet. Move a coil or plug on the 2018 Honda Civic if it's cylinder-specific and see whether the code follows. Save the big job until that test fails. If it doesn't change the out-the-door or the repair estimate, it's noise. Your commute and mine probably aren't the same, but the test still applies. That's my plan before I call anyone.