I need help. I changed the oil in my car and put in royal purple 5W30 and now when I sit at idle my oil pressure drops down to the red and the light comes on. When I hit the gas my oil pressure is normal and when I first start it I have 40lbs of pressure. Any idea of what the cause is.

 

i have the exact same problem. had it for years. one day i changed the oil and from then on everytime I stopped it would redline and the check oil light would go on. the only way to get around this for me has been to use the thickest engine oil I could find. i still get really low pressure but atleast it doesnt redline. dealer couldnt tell what was wrong w/ it and said to fix it theyd have to pull the motor, so for now ive just been stickin' w/ the thick oil thing.