Sounds like either a flaky probe or EDC-D10A. I wouldn't worry about it making other things unreliable, given the nature of the reading and how it gets into the system. But, I'd first check and make sure that the OAT wiring isn't intermittent in some way. After that, I'd probably give our tech support a call at 425-402-0433 to see about troubleshooting it further if the issue continues.