Alright, so I picked up this truck back at the end of January and it wasn't throwing any codes. It had higher mileage, but I only paid 4k for it and it booked for more, not to mention no rust on the body....

Over the last three months, I've been literally pouring money into it though, and it's becoming an issue, that I need to figure out the cause of. At first it was a cluster pack, no big deal, replaced. Then it was a power-steering leak. Alright, no big deal... Then another cluster pack was what I assumed with a Misfire in 5, so I just replaced ALL of the clusters and spark plugs.

The misfire in 5 has been around for 2 out of the 3 months I've owned this truck, and no matter what I do, I can't seem to get around it. New coil, new spark, new o2 censor (since it was throwing that code too for a moment)....

Right now, it's idling a little rough with this P0305 error code, but it's manageable, and it's unnoticeable when driving, only when you're idling... Which I originally blamed on a timing chain tensioner that went bad, luckily enough I already had that fixed as well.. Yeah, 2 months in and I had to change a tensioner and have it retimed.

Now I'm getting codes
P0031
P0132
P0305 (The bane of my existence...)

It just seems like one thing after another keeps popping up, and each time I have them fixed, or it seems like I have them fixed, they pop back up with an error code. Even the local garage was confused and they did most of the work... Now, it is an R-title, so I expected some problems. But are these problems things I should take care of myself? Or should I look into the Lemon Law?..

 

Two of the codes are for your oxygen sensor. What brand did you use? If you say Bosch, change it. Dakota's hate them with a passion. Use NTK or Denso.

P0305 is the misfire on cylinder 5. How often is it misfiring? You could swap the coil pack with one from another cylinder to see if it follows. What did the plugs look like?

Pull the rocker cover too and check things thoroughly. Rocker problems DO happen.

 

I've even tried pulling the coil pack out while it was running and you couldn't tell the difference, it still ran rough. Plug it back in, stayed the same. Tried that with a different coil, completely different response. As for the plugs, I didn't get to see them, I let the garage do that while it was there.

 

Pull the valve cover.

It sounds like you have a dead cylinder. The 4.7 can/does throw rockers occasionally. It also can drop valve seats.

Check the compression.