I've got a 91 coupe, N/A. completely stock. when i first got the car, i added a grounding wire (4 gauge) from the battery to the alternator bracket. Recently i have been having some goofy electrical issues.

first, when getting in the car, all the lights will be off and turning the key to on does nothing. subsequently, it can't be started. going back to try again after a few hours, and it's fine. while driving however, the stereo and other electrics flash randomly.

today a new one started though. Opening the door caused the interior lights to go on like normal, but once it was switched into on, everything died. repeated several times until i got my volt meter and checked the battery terminals. (batt under 1 year old) terminals read 12.something so i figured try again. turned over just fine. took it for a drive and noticed that once you press the brakes in enough to get the rear lights to go on, all the lights flicker, including headlamps. this continued to occur even while the car was at 5K rpm.

before i thought i just had a short, but now it's starting to look like bad alternator, which i thought was rare, or maybe just bad wiring to it. I've lost my RX7 manual, but have a digital copy somewhere, i just hate wiring diagrams. does anyone have any idea what else the problem could be or have had a similar situation?

 

I'd say you've got bad connections somewheres, or a weak battery. The voltage should be at least 10V while starting the car, btw, or it means the battery can't handle very much current (even when charged to 12V). Try taking the battery to an auto store to test it for free. You can have them check the alt too if you want. If those are good then it's time to fiddle with the wiring. You can also pull some fuses and see if that fixes anything. If so, the name of the fuse you need to pull tells you where the problem might be.

 

Battery connections good?

 

bad battery connections

 

i thought this too. they're rock solid at the terminals, but i don't know where to look after that.

 

Have you tried cleaning them? Mine was doing the same as yours before, and the connections "looked" fine. I cleaned them up, and it hasn't given me any more problems.

 

Yep, pull the clamps off, clean (emery paper, battery post wire brush, etc) all the inside of the clamps and the posts and then re-assemble and see if that solves the issue.

 

thank you icemark, i knew there was a reason i liked you.


fwiw i used a wire brush for the terminals on the battery, but for the connectors (which i think are factory) i used a worn out .30 caliber bore brush. worked like a charm.