Lee, Deloreans don't idle very well when it comes to fuel mixture and an unheated 02 sensor. Ours is a 1 wire and depends on the exhaust heat quickly to start leaning the fuel out. . In my experience on a day like you have or had, you let it idle and the plugs kept loading up with the rich burn because it was taking to long to get hot before the 02 would kick in and cut down the rich mixture. By the time it did everything was just rich in fuel. Check out the plugs as well and be sure you have a good hot battery to start. New plugs, new 02 and a hot battery. The after it starts go out and drive it no idling and then adjust the fuel mixture to get rid of the hunting / seeking. Call if you need and further assistance. John Hervey www.specialtauto.com www.deloreanautoparts.com -----Original Message----- From: dmcnews@xxxxxxxxxxxxxxx [mailto:dmcnews@xxxxxxxxxxxxxxx] On Behalf Of Lee Edmonson Sent: Friday, January 02, 2009 3:20 PM To: dmcnews@xxxxxxxxxxxxxxx Subject: [DML] Rich Mixture + hard start Okay, so #02566 (automatic) on the Oregon coast has been running just fine on its weekly outings until recently on a cold (for the coast this is near 32 F) day when I started it normally, and while letting it come up to temperature in the garage it started running rough while doing its normal idle hunting. This roughness includes lots of black smoke at every RPM. I have read through many of the old posts about causes and cures and did not see an obvious clue as to what could change sitting in a garage for a week. This morning it would barely start and is very rough at idle with black smoke. I did not let it run very long in this condition, but probably had a total of 5 minutes of rich mixture and smoke. The second time I tried to start it today it would try to start, but would not quite make it. Has the O2 sensor been killed by the rich mixture and should it be replaced before moving on to other things? Where is the best place to start running down this issue? Lee Edmonson Vin #02566 ------------------------------------ To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnewsYahoo! Groups Links ------------------------------------ To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnewsYahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/dmcnews/join (Yahoo! ID required) <*> To change settings via email: mailto:dmcnews-digest@xxxxxxxxxxxxxxx mailto:dmcnews-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/