OK, I called a friend who makes a living diagnosing vehicle problems[other guys do the actual repairs in the shop,he diagnoses the problems]. He indicated that if both banks are lean, it is unlikely that it is the oxygen sensor. He indicated that it certainly could be a vacuum leak, most likely at [1]. Where a few hoses come together and connect, one may have fallen off or split. [2]. It may unfortunately be an intake manifold leak, especially if it has been overheated. It could be the MAS sensor, but it usually throws out a code. Did you clean it with unchlorinated brake cleaner or electrical cleaner? He indicated that if cleaned with other solutions, the electrical coating may have been broken down. These suggestions would be addressing the codes indicating a "lean" condition. The code re: the "cat" he felt was a separate problem, and may need a new "cat" after the other problem is fixed. He felt that it might be better to locate a shop that is skilled at working with the newer systems, rather then buying things you may not need, and have it "scanned" where they can read the data stream from the sensors in real time, rather than just read a trouble code like your code reader would be doing. They can find vacuum leaks with propane[speeds up the engine if the propane gets sucked in where there is a vacuum leak]or "smoke". They could tell you what the probem is, and then you could decide to fix it yourself at that point, you would just pay them for the hour or so for diagnostics. Good luck, I know this kind of thing is really frustrating. Joehawk
