Starting Problem (Electrical?)
 

I'll start of by saying I've searched and not found exactly the problem I'm having.

I have an '84 GSL-SE with a TII swap, Optima Red Top Battery, new Alternator (less than 3 months), external battery cut-off switch.

Problem is this:

RX won't start after she's been sitting for a while. Like if I'm going to work in the morning or afternoon and I havn't driven her since I got home the day before. I get in, shift to neutral turn the key and goose the gas a little and as the engine cranks, the voltage drops from 14.x down to 7 or 6 and no start. The lights dim and the cranks finally stop, like a dead battery normally would behave. A quick jump though, from another car and she starts right up. No need to leave the cables on for a couple minutes to build up a charge. Even leaving the optima on a slow charger for 24+ hrs doesn't change anything. The previous owner suggested switching the battery disconnect after getting home and then back on the next day and that sometimes helps, but not usually. Also, whether or not I need a jump to get to work, after 8-10 hrs at work, whether the disconnect switch is on or off, she starts 95% of the time on the first crank and I get home fine.

Possibly related, if I'm ever a dumbass while driving and kill the engine with poor clutch work and have to start it again (like at a light or something, yeah yeah, laugh it up), I get the same problem with the car not starting while it's cranking and the volts dropping from 14 to 7 or 6. Thankfully, I've been lucky the few times I've done it and managed to get it started before the battery gives out.

Thanks in advance for all your collective help and suggestions.

Probably either bad connections on the + and - battery cables, or the cables are corroded internally and need to be replaced. Good luck...



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