Randomly enters into limp (?) mode- rough idle

[andrewwynn]

The 02 heat won't cause limp mode my car has has that problem for 7 months.

Go-to on random limp mode is bad plug. Did you replace the plugs?

I had three of those events over about a year. "Misfire with fuel shut off"

Wife's car had it bad: couldn't drive more than about 20 miles at the end without misfire / limp.

Changed her horrible looking plugs and back to normal. I then realized probably why I would get the same exact error occasionally so I changed my plugs as well.

(No misfire since and bonus better mpg)