I had Advance pull the codes off the truck today.
Some of these were expected, others are a bit more confusing

P0351 - ignition coil A primary/secondary circuit
P1504 - Idle Air control circuit malfunction
P0171 - Bank 1 system too lean
P0303 - Cylinder 3 misfire
P0304 - Cylinder 4 Misfire
P0305 - Cylinder 5 misfire
P0308 - Cylinder 8 misfire
P0307 - Cylinder 7 misfire (pending)

I'm not sure what "pending" really means. So far, my searching indicates that the ecu "thinks" there is a misfire, but isn't 100% sure about it yet. So, we'll just assume that cylinder 7 is misfiring too.

My searching indicates that for the ECU to actually know there is a cylinder misfire, it is because the coil didn't fire properly. There really isn't any other way for the ECU to know a specific cylinder is missing otherwise. This tells me that it is likely that the new coils that are on there, are no good. Which is apparently a really common thing with these trucks.

I kinda figured the idle air control valve would throw a code since I had it unplugged with the engine running. But, the new control valve I have on there is making that same howling hum noise as the old one, if not even worse. So I wouldn't be surprised if this new one is bad too. BUT, this new one needs adjusted, and you can't really adjust it with all this misfiring going on. I was able to adjust the howl out of it, but then it wouldn't hold the idle. So, I'll work on getting this corrected once the misfire is under control.

The two codes that are really throwing me for a loop are the P0351 and the P1504.
P03051 - circuit A primary/secondary malfunction... It wouldn't surprise me that "A" = "1" heaven forbid that we keep the same numbers, But, if that is the case, then why wouldn't it just throw a P0301 - cylinder 1 misfire? What's the difference? I did some searching and I found everything from "replace all of the coils and plugs" to "replace the cam position sensor" and all points in between. Anyone really know what the P03051 code actually means?

As for the P1504 - bank 1 too lean code... which side is bank one? again, not been able to find a straight answer on this in my searching either. Personally, in my experience, this code indicates a catalytic converter issue. Which would be wonderful. FML. I would think if anything, there would have been a "too rich" condition because of all of the misfires. Unless of course the up stream o2 sensor is seeing the extra fuel from the misfires, leaning the mix out, and causing the whole thing to run lean. Which also makes sense. At least to me. I'm hoping that this is another one of those issues that can wait til the misfire is under control and hopefully isn't actually an issue.


As of right now, I had all of the codes cleared off. No codes back as of yet. It is still running crappy, stumbling all over itself. gonna try to put a few miles on it to try to make the codes come back and see what it says then.