Turn off check engine light on Jeep Wrangler - 2002 Jeep Wrangler

SOURCE: 97 wrangler oil pressure drops when engine is at idle

check the engine oil level... you could possibly need to replace the oil pump soon... if you do not live in a cold climate i would consider using 30 or 50 weight oil. do NOT use that in a cold climate as the oil is like molasses when it gets cold.
that's only temporary. one other thing to consider is a clogged oil filter... when was the last time it was changed ?

Robert

SOURCE: 1992 Jeep Wrangler 2.5L engine maintenance light needs resetting

It's a module under dash programmed to turn on Maintenance light. You can pay $80 to replace module or pull wire going to module and save $80. BTW, it's there to tell you to replace your Oxygen sensor.

SOURCE: 2002 Jeep Wrangler 4.0 When Driving the Engine Dies

Put the key in the ignition and turn it on and off (3) times without starting the jeep, leaving it in the on position count the (1) flashing indicator Light, Eg: (5) flashes, Then there will be a pause, then it may flash (3) times, this is a code #53. Keep your Eye on them and write them down. If you should miss (1) Repeat as many times as needed, Info: A #55 means there are no codes!!

SOURCE: 2006 jeep wrangler check engine light came on it

There is a software update for the PCM that addresses this issue. TSB 18-028-06

SOURCE: engine keeps missing. unknown codes

Code 1682 indicates low battery voltage. This could be a problematic alternator, which would likely cause misfiring. Autozone should be able to check this for you for free.

Code 1391 indicates the computer can not see the crank or cam sensor signal. This would likely be a result of the misfires.

Code 0320 indicates the crankshaft position sensor reference signal could not be found while the engine is cranking.

All of these issues point to either a cam/crank sensor malfunction or a charging system problem, either or both of which could cause the misfiring.