Rough idle and bad misfiring

Whats up guys, so my DD has been acting up on me... DDs arent supposed to do that right?! Its a 2000 4.0 aw4 with 136k. So out of the blue it started to idle a little rough, my tank was low so i filled it up with premium and some lucas fuel injector cleaner. Drove for a few weeks and no issues. Then it comes back worse than before. Jeep was missing very bad while going down the highway, CEL blinking and jeep wouldnt rev over 3k. Thankfully at the exit there was an advanced auto so i scanned it and the only codes were P0300, P0301, & P0304. I was about an hour away from home and didnt wanna pay for a tow so i did a hard battery reset on it and the jeep fired right up and ran like a top? So i drove the hour home, no issues, next day was driving around trying to get it to act up... nothing. Drive it to work the next day and the misfire comes back. So i did the plugs and coil pack in it. Fired it up, still had a slightly rough idle but revved fine and drove normal. Since the plugs and coils i havent driven it much due to work and not wanting to get stuck on the side of the road.... so thoughts?! I wish i had some more codes to point in a better direction. As the CEL has not come back since the new plugs and coil pack.

Thoughts?!

Here are the plugs i took out, they had about 40k on them.

Start with the basics of troubleshooting any drivability issue, test the fuel pressure, test the cam and crank sensors, test the TPS, test the O2 sensors. If the battery is more than a few years old, have it Load Tested also.

Tim_MN said:

Start with the basics of troubleshooting any drivability issue, test the fuel pressure, test the cam and crank sensors, test the TPS, test the O2 sensors. If the battery is more than a few years old, have it Load Tested also.

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true true. ive been so lazy lately with working on the damn jeeps haha but guess ya make a point :eeks1:

The not revving over 3k kinda makes me thing an IAT sensor. The clip for a few of my sensors are broken from changing them in the dead of winter and every once in a great moon my IAT will come lose. Won't rev over 3 k and runs bad.


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