You can stop at any autozone or the like and they will read the codes for you free.
Or depending on the year of your jeep just turn the key back and forth from off to on position without starting it 3 times quickly. The codes will flash in the odometer.
It sounds like you probably just muddied up your o2 sensors, but to check the code yourself turn your key to the on position,off,on,off then on. Wait a few seconds and the cel will begin to blink. count the blinks. there will be a pause between numbers. The check should end with the 55 code. You can also take to any autozone and they will check it for free.
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