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I have just bought a used 2003 Honda CRV travelled 86K, and have started to use the air blower and have noticed the catalytic converter is continually filling the cab with a sulphur smell.

As the car is still under warranty, should this be correctable or do I have to put up with it forever?

I have been told its just doing its job but if this is the case surely there would be many more complaints.

I have always used the same fuel brand as this is the only gas station in town.

Richard

From the "Ask Jack" archives - 18 December 2009

It is possible that you are talking about 2 different things.

A smell of sulphur from the catalytic convertor is normal from time to time and is more noticeable from outside the car rather than inside.

As the catalytic convertor needs to get very hot to work properly, often a lot of cold / short drives can allow the smell to be more noticeable.

The smell when the blower is turned on could be something different. Bacteria can build up on the air conditioning evaporator which can be smelt when the blower is switched on but the air conditioning isn't.

This is because when the a/c is on, any moisture on the evaporator ices up, but when it is off, the moisture molecules become airborne and can cause a smell when the blower is turned on.

If this is the case, try turning on the a/c (even if you are wanting warm air) with the blower and the smell may eventually disappear.

For this reason, many people use the a/c all the time. It also helps to clear condensation on the windows more quickly.

If the smell continues the evaporator may need to be removed and cleaned to deal with the bacteria.