2000 Plymouth Voyager

Engine Performance problem
2000 Plymouth Voyager 6 cyl Front Wheel Drive Automatic 125000 miles

I have a 2000 Plymouth grand voyager with approx 125,000 miles on it and this past week the oil light started coming on and " dinging" usually only at stop lights. I checked the oil it wa s abit low so I added a quart, got it back to proper levels and figured it was done. Well after driving it for about 30 mins it stared doing it again. Oil levels are full, so I'm not sure why the oil light would keep coming on and dinging. Please help
March 24, 2008.

Check the actual oil pressure with a mechanical gauge-if its normal-start by replacing the oil pressure sending unit

Mar 24, 2008.