tach issue
 

so my pretty much brand new autometer tach keeps messing up. it will work occassionally on start up, and then work for a while. then it will stop working. but if the lights are on or anything it will still go on (the light not the needle). all the connections are tight and everything seems to be fine. could there be some kind of problem or interference with the MSD setup im running? (6AL box, pro billet dist., wires, coil, etc.) i see in jegs and summit all sorts of converters and stuff for tachs.

The first thing I'd look for is a bad or weak ground.

Check the connection going into the MSD box as well. If you are using crimp on terminal ends check and make sure they are tight.