I had the same problem a year ago (fails on HC [and CO] on low idle). I took it to DMC Houston and they "adjust Fuel mixture" according to my invoice. This year I took it in for exhaust manifold gaskets and we found the cat was collapsed and half packed full. So you've already taken care of that-- so I'd say a fuel mixture adjustment. Does your car also do lots of idle hunting? Mine did, before the adjustment. And the exhaust was very strong fuelly smell. DMCH probably isn't convenient to you, but you can probably find someone nearby or get enough information from this list to help you adjust the fuel mixture. Sorry that I can't give you more information about the adjustment-- that is the con with living in the same metro area-- that I tend to take things to them to save myself time and curse words. :) -----Original Message----- From: rendy_cheng [mailto:rcheng@xxxx] Sent: Monday, April 22, 2002 7:20 PM To: dmcnews@xxxxxxxxxxxxxxx Subject: [DML] Re: high hydrocarbon in exhaust