My 98 quadcab recently starting losing oil pressure for about 2-3 seconds,
enough time for the gage cluster to ding twice. After dinging, the gage
goes from 0 back up to 40 lbs. It only does it at a stop at idle (and not
all the time). 81,000 miles. Could it be the pump or sending unit going
bad and how do I tell? Won't do it on highway or when moving. Has
required amount of oil in it and was changed 2 months ago.