I have been driving my 8 with no isswues for months and I parked it for a day and a half and then when I went to drive it I got it...all lights were on, dash lit up, I turned the key and the entire car power shut off. All lights, dash...everything...and I get nothing. I threw a pair of jumper cables on it and immediately I got all my lights back and while still on the cables I started it with no issues. I took it for a drive and even shut it off and restarted it with no issues.
I then sat it overnight and this morning I went to start it and got the same issue...turned the key and bang everything shut off...all interior lights and everything.

I'm now stranded.....has anyone seen this????

And of course after posting I see my typo in the heading....it's going ot be one of those days!

Ok....so I went out...and wiggled my power cable which barely moved...and it had a freaking tiny spark....then I opened up the door and everything came back online....so really annoying...hopefully I made someone laugh or say....you idiot....cause I feel like one. I will reply if it turns into anything else after work.

-- Thanks --

Ok....so I went out...and wiggled my power cable which barely moved...and it had a freaking tiny spark....then I opened up the door and everything came back online....so really annoying...hopefully I made someone laugh or say....you idiot....cause I feel like one. I will reply if it turns into anything else after work.

-- Thanks --

Your "power cable " ? What exactly are you referring to as I have had this problem before. Thanks.

I currently have an optima Red Cap battery...and when I bought it I got the wrong model meaning the terminals are on the opposite site. So The Negative still reaches with no issue....but the Positive does not. So I have a 2 Guage add on that I used to make the connection....it is a Heavy Duty custome connector I use to use in Car Stereo comps...however the crimp on the terminal side seems to be giving way a little...which seems to only happen when the car sits and cools down. In the end...fix the crimp...and I fix the problem....it seems to cause the power loss when the draw occurs from turning the key...I think it's just at the right point to cause this issue...especially when I can just apply a little bit of pressure on the crimp to make the connection strong enough to start the car...I don't even have to hold it...just push and then let go.

The battery cable terminals on the RX-8 do not fit many aftermarket batteries very well and they oftentimes are too loose to make reliable contact.

Optima actually does a great job with fitting...howeer you have to buy the correct one in order for that to apply. They are standard post mounts...so it fits fine when it's on the correct side of the battery.