2002 jeep wrangler -- check engine light and code

P0302 means number two cylinder has a misfire, due to possibly a spark plug, spark plug wire, ignition coil, fuel injector or something mechanical in the engine like a bad valve, valve spring etc. Start at the front of the engine, where all the accessories are mounted(alternator, power steering pump, etc) then count each each spark plug from left to right in normal order. The cylinder to the left will be 1, and the cylinder to the far right will be 4. When you locate number 2 cylinder, check the plug wire for damage. remove the spark plug and inspect it for wear. A new set of spark plugs and wires will probably fix your problem. Otherwise it may me a coil pack or ignition module. Hope this helps.

cylinder number 2 has a misfire