Dear Car Talk:

I have a 1991 Cadillac Eldorado with 140,000 miles on it. About a year ago, I began having problems with my starter. When I would try to start my car, sometimes it would start right up, and other times the starter would click several times and then start. My mechanic recommended that I replace the starter, so I did. The starter worked fine for several days, and after several days of working fine, the same problem returned. I replaced my battery with a new one, and had two different auto stores run a test on my starter, alternator and battery. The tests indicated that they were all in good shape. What else could be causing this problem? Could it be my battery cables or my ignition switch? Please give me your professional opinion. — Joseph

I doubt it’s your battery cable’s terminal ends. Since you had the battery replaced, the mechanic almost certainly made sure the connections were clean and tight. That’s standard procedure.

So, based on the age of the car, I would lean more toward a ground problem. There are ground cables that run from the battery to the chassis, and from the chassis to the engine block. That completes the starting circuit. And unless those ground cables are making good, solid contact, allowing the electrons to make their way back from the starter to the battery, the car won’t start, and you’ll get a clicking noise.

And it’s entirely possible that those ground connections have started to corrode.

When a car is old enough that you can see the ground through the floor of the car, it suggests that your ground connections may be perilous, too. And if the ground connection is corroded, rather than completely detached, that could explain why the problem is intermittent.

If I were you, I’d just have my mechanic run a new ground cable. I’d run it from the negative terminal of the battery right to the engine block, where the starter is bolted to the block. That’ll guarantee that the electrons will have a good path back to the battery.

If that doesn’t fix it, Joseph, the next thing I’d look at would be a bad neutral safety switch, which requires the transmission to be in neutral or park before it allows the car to start. Those can fail intermittently. Or you could have a bad or corroded connection somewhere else in the ignition system. But try the ground first.

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