My check engine light came on a few weeks ago. Codes for random misfire and misfire in cylinders 1,2,3,4,5&6. the car has long starts maybe 10% of the time and idles rough but accelerates fine and drives fine. and only noticeable misfire is when driving at highway speeds at around 1,000 to 2,000 rpm it sputters and misfires. disconnected the battery and plugged it back in because i heard that it could have been a heat soak causing the misfires. went away for a few days and came back with the same codes. cleaned up the distributor cap, new plugs, sea foam, oil change it went away. came back on today and havent gotten it read again yet. but would guess that its still those codes. could this be the coil? or the Crankshaft Position Sensor? ive read some of these symptoms from that, but usually they wont start at all if thats bad..? im new to jeeps so any info would be greatly appreciated.

 

When my CPS went bad it didnt make my CE light come on. Just went bad and wouldnt start. Sorry im not much more help

 

i would think that your coil may be getting weak. how are your plug wires? if the random misfire is on all cylinders, i would look at anything that is common to all cylinders, like the coil. like was said, when the CPS goes out it just flat out won't run/start.

zedpapa

 

okay thats what i thought bout the cps. thanks for the help guys. ill do coil today and see where im at

 

Sounds to me like your o2 censor sometimes you can pull them out and do the old spray shake and repeat with brake cleaner. The thing gets all gummed up with carbon there's a little bb inside you should here it rattle. If you can't clean it $57 around here anyway.

 

the last owner replaced the o2 sensor in February along with muf and cat i believe. so it should be good. i put a new cap and rotor on today. the engine light went off again. ill see what happens before i put the coil on.. if i dont need it thats $32 back in my pocket..