exhaust noise and sulfur smell

[toyota03]

I have a 2003 v6 4runner limited and i noticed a noise that comes from under the vehicule when i accelarate with the front windows down. Its and annoying rattling sound that echoes only if you are in enclosed area (meaning local streets with cars around you) at the same time givings me a rotten egg smell if i accelarate to hard. I think its coming from the exhaust converter or exhaust gasket.I took to the dealer a test drove an another v6 it did the same thing, but you cant tell me that a new suv can sound like a diesel engines does in the winter. Anyone notice the same thing or has a solution for this thanx.

[Brian R.]

The smell is a known problem that is related to the catalyst in the cat converter. The smell comes from how the catalyst interacts with the sulfur in the gasoline you use. Some people have had luck in getting rid of the smell by using high quality gasoline from Shell, BP, SUNOCO. Their high-octane gasoline is their best (lowest sulfur content) formulation.

Here is an entire topic devoted to this problem.
http://townhall-talk.edmunds.com/[email protected]/0

The noise you hear is also a problem some experience, but I have not seen a good explanation as to its origin. Here is a topic that discusses it. Not with much concrete solutions that I have seen.
http://townhall-talk.edmunds.com/[email protected]/0