Does a single misfire mandate a tuneup?

I have a 2007 Toyota Prius with just under 30,000 miles. Yes, I don’t drive all that much, which makes the Prius the perfect car. I get it serviced every 6 months by the dealer. So far, other than oil changes, the only actual maintenance has been tires, a 12 volt battery, and a $300 “inspection”.

A few weeks ago the “Check Engine” light came on. I pulled the code P0301, which translated to “Misfire on cylinder 1”. The car was running great at that time, and since clearing the code it has continued to run without the light coming on again. Given that my maintenance is more time-related than mileage-related, it’s possible that the ignition system needs attention. However I’m reluctant to bring that up at my next maintenance appointment, because the guy writing up the service order will always answer “Yes” to every “Do I need …” question.


I would wait and see if the Check Engine light comes on again with another misfire code. If it does, then I would bring it in to find out what’s causing the code. Otherwise, keep driving it.


Since you don’t drive it that much, and probably on a lot of short trips, the gas engine probably doesn’t run all that much and may never get fully warmed up. I’d consider dumping a bottle of Techron fuel system cleaner in the gas tank and give it a nice long highway run to heat things up and get the carbon out of it.