Hello everyone, new member here. I have a 200 Durango 5.9 and recently the CEL went on. I had it check by a dealership and they said it was a misfire on #6 cylinder. They said they counted 3 misfires but then it stopped. They cleared the code and said hopefully it's just a piece of carbon that got in the spark plug. I changed all the plugs and drove the truck afew miles and then the CEL went on again. Any ideas of what's going on?. Any help is greatly appreciated. Code that came up is P0306

 

First things first. Take it to Autozone, they can check the code again too see if it the same code again. If it is then you might have more detailed troubleshooting. A/Z codes also come with recommended repair options. Get the code from them and let us know. Most CEL's(Malfunction indicator Lamp or M.I.L in their manuals and your owners manual.) are usually sensor related, and if it caught right away usually no big deal. Make sure you get a printout with the code and let us know.

Good Luck!!

 

Welcome to DF
Does your truck have high mileage on it, over 70k? Here's a short cut from doing the tune-up and replacing the plenum gasket. Because i have seen this problem on all 3.9, 5.2 and 5.9L engines. Replace the cylinder heads. The valve seats drop or cracks between the valve seats, and burnt valves.

 

Code is P0306

 

P0306 Cylinder #6 Misfire


What plugs did you install?

 

I put in AC Delco as that's what the guy at Autozone said the truck needs.

 

And yes it is the platinum plugs.

 

Well there is your problem then.

Platinum is only for paint, not plugs.

IndyD

 

I saw that post and tried to warn them but got distracted.......You woke the sleeping bear Mr. Platinum man....

Start with returning the platinum plugs

Champion Copper or Truck plugs. I am not sure of the number for the 5.9 as I am a mere 4.7 scum.

Quick get them returned before Hydra sees this post. He will have a coronary and fall face first in his jack and coke.

 

To late!.....


Well I guess I don't need to go there cause I already did.....



+3 on the removal of the POS plugs. The only thing those good for is a paper weight on these motors.