oil pressure drops from 40lbs gradually to zero then starts tapping, shut it off for a couple of minutes and its at 40 again for lets say 5 to 7 miles starts dropping again
Check your oil. Is it low? If so add oil and try it. How long since oil and filter change? Oil filter could be stopped up or oil pump failing. Continued driving it like this will blow the motor so check it out ASAP.
I think your oil pressure sending unit is bad. Try and replace thar. Something is wrong in that line.
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