I have a 2005 Dakota SLT with the 4.7. It has 125000 miles. Recently it started misfiring and throwing a random cylinder misfire code along with a O2 sensor code. The problem presents itself after a cold start, usually within the first 1-2 minutes of driving. It will misfire for 30-40 seconds and recover or "fix itself" if you will. After the initial misfire, it will not happen again until the next cold start. The severity of the misfire is random. Sometimes it will be so severe that the check engine light will flash. Other times not so bad. The check engine light is constant due to the random misfire code.

What I have done:

- Replaced O2 sensor since I was getting a code for it. Still getting P0300 code and different O2 sensor code.
- Replaced another O2 sensor. No Luck
- New Spark plugs
- Replace throttle position sensor
- 4 Coil packs on one side of the engine

Nothing has improved the problem. Before I dump more money and replace more parts I thought I would post my problem and get some expert advice.

 

Here's some reading material for you, this issue has come up before. Hopefully something in there helps.

https://dodgeforum.com/forum/3rd-gen...e-p0300-2.html

https://dodgeforum.com/forum/3rd-gen...-detected.html

https://dodgeforum.com/forum/3rd-gen...-detected.html

https://dodgeforum.com/forum/3rd-gen...0300-code.html

https://dodgeforum.com/forum/3rd-gen...re-puzzle.html

https://dodgeforum.com/forum/3rd-gen...magnum-v8.html

https://dodgeforum.com/forum/3rd-gen...300-issue.html

 

 

Don't overlook the simple stuff.

Battery fully charged and load tested,terminals real clean and tight.

Engine grounds clean and tight.

No air or vacuum leaks,check air cleaner snorkel,pcv system,and intake manifold for leaks.

Clean mass air flow sensor.

 

heres one, my truck misfire and sucked the valve seat into the motor, you my have some issues like that going on, might want to pull the valve cover and see if have any rockers that are loose or sitting inside the tray.