David, The CO adjust screw in a conical head with a 3 mm Allen fitting. To block the hole use anything that will seal the hole, golf tee, machine screw,dowel, etc.. "We're here to help you" DMC Help / De Lorean Services / <dmchelp@xxxx> Web Site: <www.deloreanservices.com> ----- Original Message ----- From: <Delorean17@xxxx> To: <dmcnews@xxxxxxxxxxxxxxx> Sent: Tuesday, February 20, 2001 6:42 PM Subject: [DML] co mix screw > Hello, > I have been working on my project car for some time now and havent been > able to figure out its odd idle and poor acceleration problems. The frequency > valve is working properly so I thought the problem may be related to the > intake system. > I thought it might be a good idea to check the co levels and adjust the > screw as necessary. I removed the intake(both halves) and found that the > metal ball(plug) that covers the hole was missing(nice sized vacuum leak I > guess). It also looks like the screw is in as far as it can go. I am > guessing this could be my problem although I dont know for sure. Where can I > buy one of these plugs at? also, what type of head is on the co mix screw? > you cant really see it through that little hole. > > Thanks > David