So I bought a used 2004 pontiac grand prix with 239k miles on it a year ago. I got a low oil level light on and low oil pressure light on a couple times and added oil. I checked oil again after I drove it to work and it sat for 9 hours without a start and checked the oil again and its way over full. Now me being a mechanic ive never seen this happen but from whats happened I'm assuming there is too much sludge built up and its causing a draining issue back to the oil pan but dont know how to fix the issue without a flush or a complete rebuild which I dont want to do. Ive changed the oil and filters regularly with 5w30 non synth oil and ive never had an issue until the oil level and pressure lights popped up on the message center.