I blew some carb cleaner in a small hole in the sensor. It worked for a short time, then went intermittent then stopped again. Impossible to find a replacement. Called Mercedes parts and got the original parts # 123 830 03 72 searched by part# and found original Mercedes part on EBAY $139.00. Got it ordered and will recei8ve on next Friday. This is probity the last one on the planet.
Thanks again