Its probably lifter noise,check what grade of oil is in the car or change it to a slightly thicker grade,i would expect that the car has a lot of mileage on it,if the oil light goes out quickly on the dash when starting its not the oil pump(very uncommon),knock sensor is for ignition timing to stop pinging,nothing to do with your noise,generally its engine wear
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Its probably lifter noise,check what grade of oil is in the car or change it to a slightly thicker grade,i would expect that the car has a lot of mileage on it,if the oil light goes out quickly on the dash when starting its not the oil pump(very uncommon),knock sensor is for ignition timing to stop pinging,nothing to do with your noise,generally its engine wear