CEL won't seem to go off even after fixing the TPS. Today I went and got it scanned and it came up with P0121 and P0420 on the symptoms it said that a large vacuum leak can be the cause, anyone know a good place to start, which vacuums are prone to go bad? Also would like to add I don't think the cat is going out because it doesn't give off the "rotten egg" odor at all.