hi everyone, im new to the jeep forum cause ive been having a little problem with this 2003 jeep liberty i bought for my wife. when i bought the jeep it ran very nice but it had a check engine light on, but it ran good so i didnt worry about it. after a few days i went to discount auto parts to read the code(s) to see if i could get rid of that check engine light. i check, it said misfire from cyl 1 & 2, so i replaced both the coil and spark plug for those two cyl, after i gave the scanner back the jeep didnt want to start then i took it home let it sit then came back the next day and it fired right up. b ut i now runs like crap, vibrating real bad like a really bad misfire, but now it doesnt throw ne codes just idles real bad, and after it warms up it wont stay on unless i keep my foot on the gas, i have no clue what to do, next step is to take it to the dealer and wait to c how sore my *** will be wen they're done with me. Help me please.!!