Elvis Nocita wrote: >And still - a good control loop can compensate any hunting of the idle, >especially the bad ones that let the idle vary with about 1Hz. > >There's absolutely no reason or explanation behind an idle speed hunting > It's simply down to the speed at which the auxiliary air valve can move. Modern engines use ignitionadvance/retard to fine-tune engine speed, and the aux air valve is just for coarse adjustments. That coarse (slow) adjustment is all we have. >And also there's a diference between cold and warm ! Sometimes when cold >the engine may hunt very bad but suddenly stopps to hunt when it gets warm. > The point at which it stops is the point at which the lambda system switches into active mixture control - proving that the hunting is caused by a rich mixture in the first place. This is normal on an original DeLorean engine. I agree with you that a vac leak will not cause our typical hunting. Martin 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/dmcnews Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> 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/