BMW Repair: engine slug, worst case scenario, mileage cars

Question
i got a 1999 528i bmw engine light is on got camsaft senors done light still on boght to local shop the tell me car has a lot of engine slug from neglect from previse owner just bought the car and you know the "AS IS" claus but was told that a good engine flush could do the trick car runs great no lost of speed, smooth please give me your best advice before i spend 401k on this car i really love it but car,401k car 401k hmmmmmmmmm!and the car has 121165 miles

Answer
David, change the oil and filter and use some engine flush product in the new oil. Drive the car for a couple days. Change the oil and filter again and use more engine flush. Some people put a little ATF in the oil because it has so much detergent in it. Do this until you are satisfied with the color and consistency of the oil you drain out,then  have the Valve cover and spark plug tube gaskets changed. You will be able to see the complete upper valve train with the valve cover off. (The gaskets harden and leak anyway on higher mileage cars). You will be able to see if your efforts have worked. Worst case scenario is you may have to pull the cylinder head off and have it cleaned by a machine shop if the flushing doesn't work. Good luck.
-Evan