CEL came on last week. Truck is running very rough, shakes at stop lights, hesitates when taking off.

Pulled a P0306 code off of it yesterday. Changed spark plug, it was white. Cleared the code, now it's back on after driving 5 miles and running rough again. We have changed the Ignition Coils & Spark plus (not the wires yet).

I'm trying to sell it and have no idea where to go next with it.

Any help or suggestions would be greatly appreciated.

 

Strange. When I had a misfire code, I found the porcelain was cracked on that plug. And I'm talking like a hairline crack that I really had to look hard to see. I'm thinking I must have cracked it putting it in.
What plugs did you put in it? Everyone says put the autolite plugs in it, but I found those to be complete junk. I put a set of motorcrafts back in and it ran great with no more problems.

 

It's a mystery lol. I've read so many forums that people have the same problem and no one seems to know the issue.

I used Autolite for the spark plugs. I just replaced the spark plug wire , cleared the code and took it for a test drive. Light stayed off and it seems to be running 100% better. I guess i'll have to see if it last.

Thanks for the help.

 

Hopefully that does it.

 

Thanks for share the post with us.............