I'm not one to give up easily, but ...

I need to figure out quickly whether to cut my losses or keep going:

The Datsun had more electrical problems tonight. It stalled on highway 280 in Daly City, leaving me to wait in the cold, misty air for two hours to get a tow truck. I have further hunches as to what's wrong but not a lot of time over the next two weeks to investigate.

More on this later.