Starter or solenoid? Hot...no start $#@%&!

[ss427copo]

Okay....whose been here and fixed it? On mt Impala,
Most times when hot and a few times cool, hit the key....nada Lights don't dim...solenoid doesn't engage.

Connections are good, battery is new, cables are newer. When it does this, I put the big charger on it and high amp it, BOOM...cracks perect.

Anyone fixed theirs before I go nuts? Of course, it never does it when I wanna put a volt meter on it, so HELP!
(auto trans, so the weak link, neutral saftey ain't the problem like on 4-spds)

Jeff x2