my 2000 2.4dohc has issues. when i take the oil fill cap off, i can feel a lot of pressure pushing out. also, the throttle body has a film of oil on the inside metal walls and oil in the air cleaner hose. the previous owner took the cat. convert out and just ran a pipe in it's place and there is dirty water spots behind the car when it is sat and idled. can anyone help me with this?