My service engine soon light comes and goes. The other day I had new tires put on the Roady, and while it was at the shop I asked them to find out why. They tested it and said the code said the MAF sensor was bad. I replaced it about 2 years ago with a NAPA part, but got another one anyway. The light is still coming on. Now, here is my question; I think I may have a broken exhaust manifold bolt. When the car is cold, it is a little throaty, and once it warms up I don't notice it. Could that exhaust leak (if there is indeed one) cause the code I'm seeing? Any other thoughts? I guess I'm going have to break down and get my own OBD II tester.