Diagnostic assistance needed

[CollapsedNut]

There are 3 O2 sensors on V6/V8 engines
Bank 1 sensor 1 (exhaust manifold)
Bank 1 sensor 2 (this is behind the Cat converter)
Bank 2 sensor 1(exhaust manifold)

Bank 1 sensor 2 is often confused with Bank 2 sensor 1, and a rich condition on this sensor means Cat converter isn't working right

I only have two O2 sensors, and my wiring diagrams doesn't show a third for my particular vehicle.

 

[CollapsedNut]

Sounds like you are having an ignition misfire. Without any test equipment and data my best guess would be the coil pack is bad. The coil pack has 3 coils in it and if one of them shorts it will take out 2 cylinders.

I wouldn't really worry about the codes right now because a misfire can cause rich and lean codes.

I think I'ma have to say you're on the right track. While running diagnostics the other day I had the truck running for a good while and holding rpm around 2-3k, as it got warmer it got worse and gave a noticable sound difference, but it didn't sound like a miss. I can pull plug wires off with the engine running and it acts/sounds totally different. Honestly it sounded like timing was WAY retarded. I'm about to replace the coil just the eliminate it though, cause it could be doing something funny. But I guess the key here is I do have spark on all plugs, but once the coil pack gets hot it could be breaking up.

 

[CollapsedNut]

Just replaced the coil. No change. I tested the TPS and MAF, both voltages were right in spec. This pretty much settles it for me, I think it's the PCM.

 

[TrexMex]

I dunno if this will help you but it seems to deal with high idling/lean mix as well:

http://www.therangerstation.com/forums/showthread.php?p=1413315#post1413315

Comes from the 3.0 Forum