Sulfur smell

[Newport]

Found the following statement on http://www.findarticles.comExhaust odor.
Had the same issue the first 6-8 months of owining my new 2003 Vibe, and was advised verbatim as below. The smell did go away - after about a year. I have always used the same gas station, so it is not the gas.

It won't be very long before the owner of a 2003 Pontiac Vibe comes wandering in, say, for an oil change, only to complain of a "rotten egg" smell emanating from the vehicle's exhaust. With a little prompting, he may tell you that the odor is most noticeable when coming to a stop, during hard accelerations or on vehicle startup. What can you do to help alleviate the problem? Nothing, because according to Pontiac, it isn't a problem at all!

Pontiac engineers say that a sulfur-type exhaust smell is a normal byproduct of efficient catalytic converter operation. Furthermore, the odor "is neither an indication of an engine concern nor the cause of reduced driveability or durability of an engine or any of its emissions components." The reason a sulfur odor is more pronounced on a newer vehicle, says Pontiac, is that the catalytic converter is operating at its maximum efficiency. As a vehicle ages, the odor will not occur as often or be as noticeable, as the converter's substrates deteriorate through normal aging.

You can help your customer deal with the situation by informing him that sulfur compounds are present in all fuels. Because some fuels contain more sulfur than others, however, suggest he by a few tankfuls of a different brand of gasoline to see if that has any noticeable effect on the odor. Finally, point out that conditions such as extended idling, hard braking, aggressive acceleration and long periods of wide-open throttle operation usually intensify cat odors. Staying out of these drive cycles, wherever possible, should help reduce the frequency and intensity of the odor.