I recently went through inspection and I failed emissions because of an engine misfire. The codes are p0300, p0301, p0302, p0303, p0304, p0305, and p0306. With all six cylinders misfiring, I should not be able to drive my jeep. It runs fine, and I have been monitoring my MPG (about 20hwy). There are no acceleration issues, and the engine is not cutting out on me. What could be the problem?? Thank you
Misfire Codes on 1997 Jeep Wrangler
by jlipski in Cranbury, NJ on February 17, 2011
ANSWER by Johnny Mopar , February 18, 2011
You may possibly have an issue with the crankshaft position sensor. The Crank Position Sensor measures the time between each cylinder firing. If the firing pulses are uneven for what ever reason, be it compression, worn spark plug, ignition wire etc, a misfire code will be set, usually for one or 2 ajacent cylinders. For the PCM to record all 6 cylinders as active misfires and the engine runs smoothly, I would suspect the Crank Sensor, camshaft sensr in the Distributor, wiring or PCM. Make sure the engine is mechanically sound before chasing electrical issues, ie spark plugs, compression and ignition.