I am so confused by this car (1982 Firebird, 5.0 auto). Changed the passenger side valve cover gasket the other day, of course had to disconnect a bunch of stuff to get the cover off. The car was starting up no problem just before that. Once I got everything put back together, the car wouldn’t start, it just gave me a quick clicking sound. Battery shows full charge with multimeter and at the gauge, and lights and everything worked fine. Thought that maybe I had put something back together incorrectly so I dug around for a few hours trying to figure it out, no luck. Now the battery at the gauge is showing around 8 volts (but still moves up a bit, so it’s not like it’s disconnected) and the lights do not work, but it is still reading full charge with the multimeter. It also won’t do the clicking noise when I turn the key anymore. What the heck did I do? I’m in over my head when it comes to trying to work on this car, so I appreciate the help of the forum.

 

Your battery had just enough charge to make the solenoid click open and closed quickly. Now it doesn't have enough to do that. Charge or replace your battery.

 

Indeed, what the heck did you do is the question. For starters, what exactly did you disconnect when taking off the passenger valve cover? You disconnected a "bunch of stuff" and immediately I am thinking your fusible link was compromised. Which lights aren't working exactly; the dash, interior, headlights, or all of the above? Perhaps try to give the engine a jump start with another vehicle to see if the engine will at least try to turn over...

- Rob

 

This was it, charged the battery and it started right up. I thought that since it was showing 12.6 volts with the multimeter at the terminals that it was charged.

 

Good job! Now get her back out on the road...

 

Even a battery that is 99% dead will show 12 volts on a multimeter. What it doesn't have is the ability to provide enough amps to do much more than move the needle on a multimeter.