Thanks for the response. Forgot to mention that at no time did I get a code from the computer or Check Engine light. I would like to get the thing hooked up to a diagnostic device, but need to get it mobile first.
My next action will be to remove and test all of the sensors. Was hoping someone has a notion from the info I have assembled, which one could cause these symptoms, so I'll know where to start - as opposed to the "poking and hoping" approach.