Will check that tube if it ever stops raining. I know it's not the O2 because that's just the messenger of the bad news. Previous owner swapped the MAF already, I cleaned it again and so far after 80 miles it has stayed out. MAF didn't look dirty to me.... Wouldn't a bad TB gasket have showed up with the cleaner. should i open it up anyway and give it a good cleaning. One more Q. Would lower grade gasoline trip this light also?