Just recently installed an Autometer tach (#2888) that simply will not work for me. Came with a sensor probe that straps onto the alternator. Instructions say to position probe over the laminations of the alt. I have tried every possible position and it will not work. Contacted Autometer who in turn sent me a new sensor probe with wiring at no charge; still doesn't work. My alt. is the factory one and has no laminations. Autometer insists it is the correct application for my rig. When contacting the performance auto shop where I purchased it, they refer me to Autometer. The tach has been on display on my dash for a few weeks due to limited time to attempt to work on it. It has worked irratically in the past for a few seconds and then it just quits and returns to '0'. Anyone with solutions? '92 W250 LE w/ dually conversion. 
