Et al;

Car serviced for codes P0171, 174, 121 and P1793 and oil and filter change. Found a brake vac line loose under the throttle body and reconneted it and replaced Spark plugs-they were due (219K Miles on her and 50K on the last set of plugs). Coming home last night -40 miles from Port St Joe to Panama City baby went into limp home mode and also shut down my head lights, but my fog lights worked so I was still good to go and the code was a tranny fault (1793). All the codes above except the 1793 code went away after that maintenance exercise. I removed thottle body intake plastic, degreased and generally cleaned everything down to the bare plastic and went over every inch looking for leaks, checked MAF and put RTV on anything that even looked like it was trying to be an issue as far as a leak went, replaced hose just because I didn't like the looks of it and checked every hose I could find, today. Did these checks and cannot get it to fail and was wondering if anyone had a similar occurence and what was the ultimate solution if any or was it just an accidental finding and fixing. I've sent a note to the Jag folks in Mobile but response exceptations are low to unlikely except sales types.