My stock tach will work fine if I have parking and driving lights off. But will not work till about 1.5k if I have the parking lights on, and will not work at all if the driving lights are on. All this happend after the install of Megasquirt fuel controler. Tach signal is being pulled off the trailing coils.. Fuel computer gets tach signal no mater if lights are on or off. If I unplug the tach signal for the fuel computer while lights are on, the stock tach will start operating.

Is this a common problem for 2nd Gens? Might happend with after market tachs..

What is the cause of this problem? I tryed searching, but didn't find a thing.

Any help or ideas is greatly apreciated. Thanks.

 

bump

 

anyone?

 

No, it is almost certainly a wiring mistake. The tacho and lighting circuits are not normally connected in any way, so something has changed with the MegaSquirt install.