I’ve a Ford Ranger … the mechanics have taken off the ground lead of my battery so often that it no longer fits well … it remains loose even when the bolt is tightened down. One day the motor wouldn’t crank … so … like a guy … opened the hood, wiggled the battery connectors & heard the radio come on. When I slammed the hood … the radio went off.
Eventually I figured out, all I had to do was slam the car door again to wiggle it enough to start the engine. Once started, motor vibrations would keep it connected.
Sometimes, I’d get in, slam the door & a working radio would go off … so it just takes another slam to fire up the motor. Now, if the radio works when I get in … I start the motor before I close the door.
That certainly is a unique situation. Why have the mechanics taken off your ground lead so often? A new negative cable is not so expensive to replace, go for it.
Sounds like the car in “Back to the Future”. I had this happen to me . . . a college friend stopped at my house on his way back to his parents house one Chistmas, driving some type of Audi, its been a few years. Anyway, when he got ready to leave after spending the night, he tried to start the car and “click”. I went over everything I could think of . . . slammed the hood and it started. He took off and drove the rest of the way home, without incident. Electrical stuff is like that. My advice is to look at everything you can electrical, clean it twice, make certain that it is tight, and keep an eye on it. You’ll figure it out. Might be as simpe here as a new battery connection. Good luck! Rocketman