please help with tach/MSD question
 

I just installed an MSD 6AL ignition system in my 1984 Mustang and all is fine except the stock tach no longer functions. The instructions say to connect the green wire from the stock coil to the tach output on the MSD box and that no adapter is neccesary.

When I start the car the tach works for about a second and quits..if I shut it down and restart same thing.

Has anyone had this experience? or know how to correct it?

Thanks

I installed an MSD digital 6 on my 83 and had the same problem. You need an MSD tach adaptor. Im not sure of the Part number but check your directions under trouble shooting it will give a chart for your application.

Thanks very much...you're right about the adaptor, I misread the instructions. Since I can get an aftermarket tach for about the same as the price of the adaptor I needed I opted for the new tach.

My '85 was the same way with the MSD. I have an Autometer tach connected to the tach output on the MSD box, but wanted the stock one to work also. Put the tach adaptor on and they both work fine.