RIP,
A good friend that has a shop, just ran into the exact same issue. He proved it to me with his scanner. It showed that the PCM thought it was running on E85. He frequently uses a website called Direct Hit. I am checking into it. I think there is a monthly fee, of course, but might be well worth it!!
Chad,
(E85 is 85% ethanol) compared to the typical 10 or 15% ethanol-gas mixture