odor at exhaust pipe

[julius <elprofe@caribe.net>]

MODELS:ALL
CONDITION
Under certain operating condition, a "rotten egg" odor may emanate from
tail pipe.
CAUSE
*sulfur content of gasoline
*the characteristic of catalytic converters to store sulfur
compound{SO3} and release them during rich engine condition i.e.,idle or
heavy acceleration.
Under relatively rich engine running condition(idling or heavy
acceleration)sulfur trioxide is converyed into hydrogen sulfide(H2S)
within the catalityc converted.Hydrogen sulfide has the characteristic
rotten egg.
SERVICE: Recommend to the custumer to try different brand of gasoline
Generally premium grade fuel have less sulfur content than regular
unleaded fuels
It may take several tank of a different brand before a change might be
detected
The "rotten egg" odor will tend to lessen as the catalytic converte ages
Hydrogen sulfide odor is usualy less noticeable on vehicles with more
than 6 thousand miles.
It should also be noted that sulfur content of gasoline can vary from
one geographic area to another....