So, just to update the thread, I finally gave in and took it to a shop. Here's the word.


  • The EGR valve itself is fine, but the EGR solenoid is bad.
  • My TPS is bad, it has a number of drop-outs in what should be a smooth linear change in voltage.
  • O2 sensor is bad, it's probably the original one from the factory


The shop is tracking down parts. They have a supplier who says they can get the parts, but they didn't get prices back to the shop before they closed today. I'm expecting this to not be cheap, but I am running out of time to get the vehicle registered. I'm traveling on business the next two weeks, so no way I had to keep chasing the gremlins.

Same shop is also replacing the flex-pipe in the exhaust system.

When all is done, hopefully I will have a perfectly running 90K mile truck!! It will still be ugly, but who cares.