I think I have an O.K. mechanic, but I just can't quite understand everything that's going on with my benz. My "86" 420SEL has been in the shop for well over a month now because my speedometer just stopped working. The other gauges in the dash work fine, just not the speedometer. The mechanic says I need a speedometer or as he put it a "Speed Control," and also an idler. He explained that everything works off the computer. Can the computer have a glitch? He has been unsucessful in locating these parts to complete the job. Is my benz ready for the salvage yard? I tried to email a picture of the benz with this post, but it didn't work. What would you guys do? I have called a few other MB shops and they have not gotten back with me.