My cel came on during a road trip. My obd adapter said misfire #4 cylinder. The car runs smooth and I had replaced the plugs recently. Any ideas? How dependable are the injectors on the 2.5L? I ran it in the dark and did not see any sparking under the hood trying to see if it might be a plug wire.

 

It can be a bad cap/rotor/distro/plug wires/plugs/oil in plug wells or a clogged fuel injector
if you suspect injector move it to another . clear code and see if the trouble follows

 

I removed the new plug and cleaned it in my Dad's old school plug cleaner. It is a plug sand blaster from many years ago. Cel turned off today by itself. May be something causing it to foul. If it happens again, I will dig deeper.