Checking the oil level with the engine running is irrelevant and means nothing. It should go down when the oil pump is picking it up and sending it around the engine. When the warning light turns on, you have a pressure problem. That is often caused by nothing more than a faulty sending unit, but it can be due to worn engine bearings too. Your mechanic will start by measuring the actual oil pressure with a mechanical gauge. If it's okay, the sending unit is suspect.
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Thursday, February 9th, 2012 AT 5:39 AM