I have a 86 Trans Am 305 tpi, car runs great no problems. But last week it would not start, just made the clicking sound. Jump started it and was fine for about a week. Yesterday I drove around for a little bit and shut it off and the same thing happened. I jump started it again and took it up to advanced and the battery and alternator were both good. So I'm not sure what the problem is, maybe starter solenoid?? Let me know what you guys think it is. Thanks!

 

Check connections - Battery, main ground, starter S terminal, and solenoid stem to start motor. If everything is intact, test solenoid coil resistance.

 

How old is the battery? Do what Vadar did, check the connections first....however the battery may be "good" and still weak. When I worked at Sears we found many batteries were good, would test good, but wouldn't be strong enough to start the cars, especially after the first cold snap rolled in, especially the older batteries (3+ years old).

 

Battery is about 3 years old, when I checked it with the car off it had around 12v. I will check the connections like Vader said. Thanks.