I started the truck yesterday and got a check engine light and a rough running engine. The day before the truck was running like a clock cruising at 85mph or at idle. The truck has 58,000 miles on the clock.

I pulled the following codes:
P1300 Ignition System Misfire
P0306 Cyl #6 Misfire
P030o Random/Multiple Cyl Misfire
P0301 Cyl #1 Misfire

I read that the plug wires and plugs could be the cause but my brain can't get around that since it was a sudden thing. I also read where another forum member had a similar problem and the problem wound up being the coil pack shared by the two affected cylinders.

I did notice a small valve cover gasket leak.

I will pull and inspect the plugs and post back with descriptions.

Do cylinders #1 and #6 share a coil pack.

Thanks in advance for your advise and expertice.

Chris

 

I had the exact same issue at 46K ('03) and was totally with you- I couldn't believe it was wires and plugs. It was! Mine literally started all of a sudden at a traffic light. The misfires I was getting were off the same coil, despite what everyone here said I still didn't believe it was just plugs and wires but it was.

The dealer wanted a little over $1,200 and the wires weren;t covered under warranty. Ordered the Magnecors and LR Plugs and manifold gasket from RoverConnection and did it myself and have not had a prob since. Some have said it is not necessary to remove the intake manifold and have had luck but I didn't find removal to be a big enough PITA to outweigh the frustration one would encounter by not removing it. Just my .02 If you do do it yourself and remove the manifold, don't forget to replace the gasket.

Oh, I forgot. When it first started I pulled the plugs on the Cyl's that were throwing the codes and they looked perfect, a little lean if anything. By the time the dealer got me in to look at it and I did the plugs and wires, all the plugs were shot.

 

I replaced the plugs and the miss is gone. TheCheck Engine Light comes on butonly after five minutes of driving. I am going to pull the codes again and see what it says now. I am also ordering the wires. I will post with the outcome.

Chris