Help neded

Something strange happend to my 308 GTSi -80. The engine works normally when cold. After getting normal working temp, it star to missfire at one half of engine. First it misfires a while, then half engine dissapeares. Changing wires at the Digiplexes, it seems that one works always, the other only with cold engine (the one giving readings to rev gauge ). I thought that it must be electronic problem with the Digiplex, giving the sympthoms when hot, but it do not get hot, and testing the failing box cold in a hot engine, it still do not work. It simply work just with cold engine.

What should I do?

 

There is a company that puts a modern update inside the old units.....

Have you checked to make sure it is getting power in, and has a good ground??

It may have just failed, after all these years....