Hello my name is Mark

I am new to the forum. I have a 1992 Golf GTI.. There are a few things that are odd about the car that make me question that it is a true GTI. One of those thing is that it is an automatic. Here is what the car is doing. I am driving down the freeway and everything is fine and then the car shuts off. It does not sputer it is just dead. I am able to restart the car most of the time. It also just won't start some times and then all of a suden it will fire. When the car runs it runs great. The shop that works on the car think it might be the digifant computer. I have tried to locate a spare in a local junkyard but every car in the junk yard has the wrong unit in it. The digifant controler in my car is Bosch part number 0 261 200 554 and I think the VW part number is 037 906 023. I think this was origanaly a Califonia car. Any ideas on what the problem could be or leads on this part would be really helpful.

Thank You