On Nov 6, 2011, at 5:14 PM, Dennis Haynes <d23haynes57@HOTMAIL.COM> wrote:

> Also, if full throttle (assuming the throttle switch is
> working) restores power that too points to an O2 sensor issue.

I once had issues while driving back from moab. Just outside of SLC it was running super rich. Soot out the tailpipe and bucking. However It did run well at full throttle.

I unplugged the o2 sensor and still had issues. It turned out to be a broken wire in the harness . It was fixed by a shop in SLC who went through all sensor wires by one. It took them around two hours and they were vanagon experienced. If there's a shop around that has experience with this type of troubleshooting it might be worthwhile to have them diagnose it this way.