Quote Originally Posted by titrisol
I doubt that,
Cat converters are killed by sulfur and other metals/nonmetals... but start the car by pushing shouldn't do it. Me guesses it has to do more with all the electronics that are found inside engines these days....
titrisol - I just found this from a uk garage website

If you attempt to bump start a car (with a run down battery) this has the same effect as a misfire. Unburnt fuel travels into the CAT and destroys the catalyst.
It says pretty much the same in my car manufacturers manual too.

whoops - wandered off topic a bit here.