Contour Enthusiasts Group Archives Forums General Troubleshooting what cuases that sulfur smell @ 3K + rpm

The sulfur smell indicates that at least one of your cats is working just fine, but that your car is running rich.

I would try to get the codes scanned. It could be due to one or more bad O2 sensors, as others have suggested. My car was making the sulfur smell for over a year before the O2 sensor became bad enough to trigger a CEL. After replacing the O2 sensor (bank 1 upstream, in my case), the CEL and sulfur smell went away and I passed the emissions test (back in Nov of '01) with flying colours. However, the smell has recently started coming back so I am going to go ahead and replace the bank 2 upstream sensor this summer.