Yeah, I've read the oil filter article. That's when I switched to the one from Napa and then got this noise. I had thought it was the filter. Usually, when I take the Fram one off (I use the one that the article says is decent) oil gets all over the place. When I removed the Napa filter, no oil spilled at all but was in the filter itself. On the Napa filter, if you tip it upside down, you can hear something in their moving. So I put back on my normal filter selection. Noise and light continues. Tried Seafoam and replaced the oil and filter again. No change. I tried the cleaner / oil change to see if any crud was getting sucked up and causing blockage but now I'm not so sure.
I don't think it's the oil pump. The start up clacking goes away when the pressure comes up, the oil pressure is in the same range and moves as it always has. You wouldn't notice a single thing outside of the start up clack and that stupid light. So, if the timing chain is old and worn and is causing the clack till oil pressure and the puter adjusts timing, that is one thing. But I don't know if the timing change by the puter when you stop is causing the light or if it's something else.

 

I hear that rattle noise at start-up, semi warm, and even when the engine is at normal temp while going through a drive through. If my timing change is bad then f*** me.

 

Would worn timing cause your timing to be so far off that you'd run rich? I just got my emissions done yesterday and barely passed. I barely made it under the limit for gases that they say is due to a rich air/fuel mix. Not sure if that's a new cat and O2 sensor or a worn timing chaing that is causing it to run that way.

 

Could the noise be a lifter?

 

That's about the best it can be described using text. +1

could be, cut could also be low oil pressure or squishy lifters causing valvetrain clatter. Other possibilities too, and i'ts really gonna require a trained ear and stethoscope to accurately diagnose.

There are several possible causes for your high CO's, but cam timing isn't one of them. If it was so far off that raw fuel was dumping into the exhaust,it'd bebecause compression was too low to ignite the mixture. Obviously since cam timing would affect all 8 cylinders, the low compression/no ignition issue would mean no start. And CMP is used to control injector timing, not pulse width. That's the responsibility of the PCM using O2, MAP (or MAF), TPS and IAT inputs combined with RPM to calculate appropriate fuel trim for optiaml A/F ratio.

Your high CO readings are going to be one of those sensors reading incorrectly, too much fuel pressureor a failing cat. can't be sure without Datastream and a spectrometer (gas analyzer) but most likely the cat. A failed o2 will cause it to run rich (open loop) but will throw a code for slow response/no response/voltage too high/low. If hte O2's are reading right and it's one of the other sensors, the PCM will throw a P0172&0173 (Too rich banks 1&2) because maximum fuel trim to the lean end has been reached and it's still running too rich.

 

The only codes I'm getting with the key cycle is 12, 37, 55. I still don't know what 37 is being caused by but I don't think it has any relation to my engine issue that's going on right now.
A month ago I tested temps on the cat and it seemed to come out ok but I guess it could still be flowing but just degrading. Also, do you think a failing EGR would do this? My exhaust temp is higher than it was when I had it tested 2 years ago. Maybe the EGR is causing both?

 

Also, to add to the symptoms, after a chilly start up this morning, I had a light trail of smoke out of my tail pipe follow me for about two blocks.