After driving for about 30 min the Low Oil Preasure light comes on when at a

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stop or idle. Had no problem untill I had the oil changed at an auto shop. they changed the oil and the light came on so they changed the oil preasure switch and the light still comes on. they told me it was because the light is just stuck. Drive it the light should go out.I did notice that the tac idle in the morning was around 700rpm and after warm up drops to around 550 / 600rpm then light comes on. Thanks so much for your time. boyce_johns@yahoo.com