Just wanted to follow up and say thanks to everyone for the insight on this problem and for the very helpful resource links. I checked the resistance across the A/F sensor heater and found it to have no resistance at all. With this data I ordered a "Denso" A/F sensor from www.Oxygensensors.com and installed it today. This seems to have fixed the problem with no check engine light after I reset everything.

Great service and communication from the guys at Oxygensensors.com!!!!

Thanks
jf
Kingsport, TN