Quote Originally Posted by Reptile View Post
I've never ever heard of this before.....please explain.
when you idle the cat gets hotter (you tend to run a bit richer, and they were designed to have airflow) that is what they always told us in the tech classes, and even when I went to independent shops the muffler reps all said the same (walker claimed over 75% of failures were due to letting the car sit and idle)