I own an 05 liberty limited 3.7L with some mods OME lift, K&N air intake, EBC rotors and pads and flowmaster muffler. When the libby was new I would get the 0305 code about every six months I thought It was because of the extreme cold weather. I would clear the code and it would not come back for a long time, I had no other symptoms rough idle or missing ,fouled plugs or smoke etc. Well yesterday the code came back and it was hot outside and the idle is rough. I tried swapping the coil pack to another cylinder I changed all the sparkplugs now I get code 0300 random cylinder misfire.
What should I try next ? Any help would be great.

Because it's not specific to a single cyldiner, it's probably not an ignition or fuel injector problem.

If you've got a good friend with a liberty you could try swapping some sensors. Try the two upstream O2 sensors and the MAP sensor. I doubt it would be the IAT, crank-position, or camshaft position sensors. The downstream O2 sensors are for checking the efficiency of your cats and even if bad would have no impact on how the truck runs.

I had the same code when I used ngk platinum plugs,I switched back to new original ngk plugs and the code never came back.

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2004 sport 3.7
OME coil lift.
Clevis lift.
Mopar skids.
5-speed manual.
235 70 17 Firestone destination AT'S on stock rims.
Gen 4.5 a-arms

Update,the 0300 code is gone and now I get the 0305 code only. I talked with a local "Jeep" guy he seems to think that my number 5 is too lean. When I took the plugs out (NGK OEM) the number 5 plug had some yellow burn like marks around the ceramic just above where ceramic meets the threaded part of the plug, none of the others had any sign on them. These plugs have 9,500 miles on them. The plugs I put in today are champions. The local guy told me to put the NGK plugs back in and try and clean the fuel injectors with some tank addtitive.
The idle is rough and if I rev the engine I feel a miss at 3500 rpm when I drive her I can feel no miss at all the engine will climb right through the powerband with no sign of a problem.