The 98-up PCM's are programmed to require the PATS sensor. I spent lots of money on the Moates Quarterhorse and programming to be able to get around it. But in the end I can see myself sending a couple PCMs to EFI GUY to get them flashed. There was a thread a few weeks back about the battery in the quarterhorse going dead every so often, and I need to change mine, which requires the QH to be reprogrammed. Takes a few seconds once the laptop is connected, but that laptop is now about 12 years old and slower than molasses in antarctica any time of the year.