csean, where there any other symptoms? Did it happen all the time or once the car was warmed up?
e46mango, I did replace the cam pos sensors, but they are not oem. Been problem free the last year and half.. but might have to go further into that.
mjlavelle, from the records I have, o2 sensors where replaced at the dealer around 30k. Car has 140k now. I will try to switch them tomorrow at work if it's slow enough.
No oil, valve cover was replaced less than a year ago. I also inspected all spark plugs and boots at least 20 times by now.. along with cleaning all the contacts on wires, and the DME relays, etc.
I replaced my fuel filter about 2 years ago, and fuel pressure regulator a year ago.
At this point, I've fixed and replaced everything that was needed and then some. When I did the ccv system, I replaced all vacuum lines while I had the intake off. Everything is connected right. I've checked and checked again just in case it wasn't.
Thanks for all the help and input so far guys. I'm going to get this fixed one way or another. I'll update when I can do some of your suggestions.