Come along on a fast and speedy diagnosis and repair of this 2000 Jeep Cherokee Classic with a 4.0 6cyl that has a single cylinder misfire and a check engine light on. Refer to your shop manual for the proper repair procedures.

50 thoughts on “Jeep cherokee misfire / skip / p0300 , p0306”
  1. Avataaar/Circle Created with python_avatars Warren Lee says:

    Good job!

  2. Avataaar/Circle Created with python_avatars Greg F says:

    Okay, I have been a mechanic for 0ver 30yrs.
    I have watched some of your videos, and, would bring things to you for repair.
    Anyone can plug a scanner in and see the codes, then start replacing parts to no end but, you double check your self and the tools you use.
    Whenever I am going to replace an expensive part, I will check several different ways to make sure that is the bad part, so as to not be a parts changer.
    Good job!
    Your a great mechanic!

  3. Avataaar/Circle Created with python_avatars Antonio Claudio Michael says:

    Nice and easy Repair Simple Diag On this one Just a bad Coil good work Eric O was very Entertaining @SouthMainAutoRepairLLC

  4. Avataaar/Circle Created with python_avatars ssetzer75 says:

    I am on my 3Rd set of replacement coil packs, failing on 6 everytime after a relatively short amount of time. 130k total miles. The original lost 5 and 6. I am searching to see if it is caused by something else.

  5. Avataaar/Circle Created with python_avatars David Bates says:

    Hi, I have a 2002 Jeep Grand Cherokee, I installed a New 4.0 after the #6 piston came apart, drove it for a month, No codes. Now have codes PO300, PO302, PO304, this tells me cylinder 2, and 4 are misfiring. I replaced the plugs (gap 0.35) and a new coil. Drove it 2 days and the codes came back, but now it is cylinder 1 through 5 misfiring. It also has a o2 sensor code PO138 Circuit High and PO141 Heater Performance, both on sensor 1 bank 2. This is the only vehicle we have. Can you help?

  6. Avataaar/Circle Created with python_avatars Richard clinton jones Jones says:

    My 2001 xj has always carried 50 psi but i use a mechanical gauge the original gauge says 10 psi i installed a brass tee at the oil sender you cant pay attention to the jeeps factory gauge it takes less than one hour to install a mechanical gauge

  7. Avataaar/Circle Created with python_avatars CashFlowWithAj says:

    Thanks man

  8. Avataaar/Circle Created with python_avatars mark gabello says:

    And that code 340 is that a cam position sensor

  9. Avataaar/Circle Created with python_avatars mark gabello says:

    Hi I have an 01 Jeep Grand Cherokee with a 6 cylinder I have a code 340 spark plugs River chain supposedly the guy took a 2-2 get this thing running right change it but I really don't know is it a hard job to take the spark plugs out

  10. Avataaar/Circle Created with python_avatars Rusted Rocker Garage says:

    i love the XJ

  11. Avataaar/Circle Created with python_avatars Terry Hesticles says:

    Soooooo much wrong in this video……

  12. Avataaar/Circle Created with python_avatars Everett Harwood says:

    The most information in a nutshell…!!!! And Polish…. No joke..!!!!!!

  13. Avataaar/Circle Created with python_avatars JJK 1 says:

    Thanks for the video Mr. O! It's still helping people after several years. Polish engineering at its finest!

    I just replaced the coil rail in my 04 grand cherokee 4.0 with 230,000 mi
    I was getting a slight miss at idle that got worse over weeks and finally threw p0306. Plugs only had 6,000 miles on them but, number 6 had hairline cracks in the porcelain (which I think were caused by a bad coil). Replacing that plug made it better at idle but it still had a miss and was knocking when giving it gas while driving.
    While I wasn't 100 % sure it was the coils, I replaced the coil rail along with new plugs and now it seems to be good

  14. Avataaar/Circle Created with python_avatars Joshua S says:

    Damn it took me a second to figure out what the hell he was doing😂 I only have one coil and a distributor😂

  15. Avataaar/Circle Created with python_avatars Billy Longley says:

    I like the RIpp coil pack conversion kit for 2000- 01 Cherokee it’s a high performance kit that is awesome “ it’s around 300 bucks

  16. Avataaar/Circle Created with python_avatars Martin Hamberger says:

    I keep forgetting to give you the thumbs up but I remember this time

  17. Avataaar/Circle Created with python_avatars Tom Beilman says:

    At least it’s not Chinese

  18. Avataaar/Circle Created with python_avatars M C Anderson says:

    I had that 'Six" in a Grand Cherokee (1996) with the 'low oil pressure'. Replaced the oil pressure sender and oil pressure was good as new.

  19. Avataaar/Circle Created with python_avatars Spinonemaster says:

    The Jeep 4.0 is notorious for fouling the oil sensor … then people replace with cheap chinese one that fail even faster … buy the good OEM or OMIX ones … and or check with a good quality external gauge …. I've got over 550 K miles on 2 of these cherokees … that 4.0 is a solid engine … it also helps to upgrade to a 4 hole injector as they have the old chrysler 1 hole unit … bosch rebuilds are good (stay away from the cheap chinese ones) the bosch rebuild are 60 bucks, most have a lifetime warranty

  20. Avataaar/Circle Created with python_avatars FAUSTO GONZALEZ says:

    Thanks Eric great job !! Is it possible the paired cylinder with the #6 coil is still operable and not creating a misfire for the paired cylinder. Was it possible to do a OHM coil reading on the #6 and compare with others for a confirmation ? Thanks again, great video !!

  21. Avataaar/Circle Created with python_avatars Ray Proctor says:

    Thanks man! Great video! Appreciate you taking the time to share your knowledge

  22. Avataaar/Circle Created with python_avatars Just_A_Catholic_Dad says:

    I got the same code on my 02 liberty and it has a tapping sound when idling and after it runs a few minutes start getting a little whitish smoke coming from the engine bay. What do you think that is?

  23. Avataaar/Circle Created with python_avatars Doug Kubash says:

    There is a chance the O2 sensor problem was a result of the misfire, Good fix!

  24. Avataaar/Circle Created with python_avatars tyci tyci says:

    Pozdrowienia z Polski

  25. Avataaar/Circle Created with python_avatars RI Aviation says:

    Those Jeep XJ 97 up oil pressure gauges are inaccurate sometimes & read low or drop off. I replace the sender no improvement. I found I had perfect oil pressure when I put a mechanical oil pressure gauge on my Jeep. About 15 lbs difference.

  26. Avataaar/Circle Created with python_avatars ANGELO Marban says:

    Awesome video, Great information… Thanks for the help.. God Bless you ❗✌❗💪❗

  27. Avataaar/Circle Created with python_avatars Frank Perino says:

    hard to C

  28. Avataaar/Circle Created with python_avatars Frank Perino says:

    Crankshaft positioning sensor worn out misfire 1 and 6

  29. Avataaar/Circle Created with python_avatars Frank Perino says:

    Crankshaft positioning sensor worn out 1 misfire 1 and 6

  30. Avataaar/Circle Created with python_avatars Captain Jazzbo says:

    Thank you for the video…helped me with my Saturn ls1. 😄👍

  31. Avataaar/Circle Created with python_avatars Scott Duffy says:

    The 1st thing you should have done with check the fuel pressure it's the fuel pump trust me

  32. Avataaar/Circle Created with python_avatars MrJoey1570 says:

    K Suspension Viper mod….your welcome

  33. Avataaar/Circle Created with python_avatars Jarrod Durant says:

    Love the video see this what I need a mechanic like you I trust u just watching this video I have blinking check engine gas smell going through my Exhaust I'm lost I smell gas on driver side not valve cover passenger side seems ok I haven't inspected anything I have to watch videos learn step at a time

  34. Avataaar/Circle Created with python_avatars Paublus Americanus AMERICANUS says:

    You know Eric you are one of the smartest troubleshooters I have watched. Usually I can be way ahead of a lot of mechs. But proving you are Polish was loosing your license one day before you got it back, burning the tires off with Dad's car. When I was a teen I broke the pickup transmission doing very similar stunts and he made me put another transmission for punishment. Taught me a bit and probably easier for me than him in his 50's.

  35. Avataaar/Circle Created with python_avatars Shane Harrison says:

    Didnt know they switched to those kind of coils all the ones I had all had plugs and wires and distributors

  36. Avataaar/Circle Created with python_avatars 8avexp says:

    My '88 Jeep has one coil and a classic distributor.

  37. Avataaar/Circle Created with python_avatars Pedro Arroyo says:

    My jeep due the same misfire 1999 jeep cherokee

  38. Avataaar/Circle Created with python_avatars Joe Jacovino says:

    have to say thanks, recieved the sma coffee cup, perfect to hold the java while checking out at your vids , thanks again

  39. Avataaar/Circle Created with python_avatars Mondyu Garvoye says:

    I have a 2015 Jeep cherokee, misfire on cylinder #2. My uncle replaced the Spark plugs and the coil and there's still a misfire on #2. What could be the problem sir?

  40. Avataaar/Circle Created with python_avatars sincitydude 72 says:

    I have random misfire problems p0300 and then p0301-p0306. I've replaced
    everything in the engine compartment including the engine itself and it's still happening. Battery, ignition coil, spark plug wires, distributor, spark plugs, fuel injectors, fuel filter, fuel pump (4yrs old),map sensor, Reman engine with cylinder head. Fuel pressure, vacuum test, compression test passed by pro shop. Can't figure it out.😬😬😬. Any suggestions are definitely welcome.