Put my 2002 xterra 3.3 on a computer and the readout said # 2 cylinder misfiring. changed plugs and wires and timeing belt rotter butting and disterrabor cap and it still misfiring on # 2 cylinder. I have ran seafoam cleaner through the tank two times helps sometimes. what next ?? Jimmy
Still is not repaired correctly. 2 years now - emissions problems. Have had an oxygen sensor replaced, all spark plugs replaced, numerous other things (hoses, belts, timing belt, radiator, power steering, center link and idler arm) just to name a few! I need help. Auto Zone codes say Knock sensor or misfire # 4 cylinder or Catalyst system efficiency below threshold. But mechanics can't seem to fix it and keep the check engine light off more than a week. It runs a little better with a full tank of high octane gas.
Clogged fuel injector causing rough idle, fouling O2 sensors (which causes check engine light) and lowers gas mileage down to 11mpg.
Same problem an that's just one of many
Not fixed yet. Misfire on Cyl 4
Problem with fuel injectors. Engine light did come on. Luckily covered under warranty.