battery seems dead after sitting for around 4 hrs, but the car still starts, but cranks really slow... not sure what else to say...

 

Alternator putting out 14 volts?

Is it a maintenance free battery (if not possibly low on water/electrolite)?

Do you have aftermarket systems that may pose parasitic draws?

You need to say allot more......

 

well havent checked the alternator but it seems to be doing it's job... it cranks like a champ while still warm. i dont have any after-market electronics installed, and the battery is the factory mazda one. well, i'll be making a trip to the auto parts store later to have my bat and alt tested, so i should have some answers then

 

I'm sure you've checked the simple things, like alternator belt tension, battery lug tightness/corrosion, trunk not ajar...

Yep, best/easiest to have Autozone or the like test your alternator output and battery capacity.

 

yup... battery's shot... terrible timing, just ordered an exhaust...

 

Great it was the most obvious thing. Lets hope thats the end of it, but if it's not all those things that HUEY52 said are good ideas!

 

Glad you found the 'easiest' solution.

btw: My OEM Interstate battery is still holding well (not bad for presumed March '05 install). But then, I had a Battery Tender on it all last Winter and will do so again this year. Will probably proactively replace it next season tho' with a Diehard Platiinum or Optima Red Top.

 

My OEM Interstate battery......

How could an OEM battery be an Interstate?

OEM is Panasonic, right?

 

My '05 (latter March build) had the upgraded starter and Interstate battery installed at the factory, thus OEM.

2004's and early 2005 builds had the original starter and a Panasonic battery. That's one way to tell if you have the older starter - Panasonic battery.

But, as a Super Mod, surely you knew all this.

 

Sorry, but there is no way an Interstate battery ever was 'OEM' in a Mazda.

Dealer installed maybe.

 

Although I let my '8 sit on the lot for ~9 months before I took delivery, I 'visited' it as soon as it came on the lot (prior to the TSB) and it had the Interstate.

Whatever.

 

New here, but the RX-8 we have is doing some weird crap.. and we haven't even driven it that much at all since buying it. Seems like one thing after another has went on since getting it from the dealer.

Battery went dead, got a new one.
Alternator went dead, new battery was drained all the way.
Took new battery to Advance Auto so they could charge it again.
Battery charged up at the store, brought it home and installed.
Drove the car maybe 5 times since then within the last couple weeks.
I moved the car the other day and it started fine.
Went to drive the car last night and it would not crank.
It would try to start, but not turn over.
I'm wondering if the battery lost it's charge again somehow from being drained before.
I can hear the fuel pump, etc. and today it seems worn down even more than last night.
Interior lights work fine, but it's really sluggish about trying to start now.

Wondering if it could be the starter? Or, if it could be just the battery. I'm going to take the battery back today to get a replacement but if it is the starter I know that's not going to help me much. Any ideas? I'm new to the rotary stuff, I have a Mazdaspeed Protege so that's where all of my knowledge lies right now.

I'm curious to find out some info regarding the "upgraded starter" for the March+ RX8's. I really can't recall what battery this one had before we switched it out. On the door sticker it says 07/04, and there is also a blue "Authorized Modification" sticker there as well.

 

Once you fully drain a non-deep cycle battery it thereafter tends not to hold a full charge (case in point for deep cycle batteries).

Be sure there isn't some other drain, such as the trunk lid beig ajar (trunk light on all night will drain the battery).

 

Thanks for that information. If by chance we do get a new battery today, I've found another likely cause..


Bulletin No: 01-048/06
2006 Mazda Motor of America, Inc.
Last Issued: 11/17/2005 Page 7 of 11

ENGINE STARTER INSPECTION / IDENTIFICATION Some vehicles will require engine starter replacement depending on VIN / production range, and / or visual identification. Use the inspection procedure below to determine if starter replacement is necessary.

AUTOMATIC TRANSMISSION VEHICLES: 1. Is the VIN at or below JM1FE17N* ** 148961?- NO – Starter replacement is not necessary, go to STEP 11 in REPAIR PROCEDURE “A”.- YES – Go to STEP 2.2. Inspect vehicle’s starter label to determine starter type. Starter label can be seen under hood on driver’s side.- If label indicates “N3H2 A”, replace starter. See workshop manual section 01-19 STARTER REMOVAL /INSTALLATION. After starter replacement, go to STEP 11 in REPAIR PROCEDURE “A”.- If label indicates “N3H2 B”, “N3Z2” or later, do not replace starter, go to STEP 11 in REPAIR PROCE-DURE “A”

 

Yep, time for the upgraded starter and battery. Actually, it should have been done long ago.

 

Yes, it definitely should have. I'm glad I found out about that from this thread. My husband (yes, I'm a chick) bought the RX-8 not too long ago. I looked on the CarFax that I ran on it today but it didn't show anything regarding the reason behind the "Authorized Modification" sticker. I'm still curious as to what they did to the car for that to be applied.

 

Here's an upgraded for sale if not still under warranty: https://www.rx8club.com/rx-8-parts-sale-wanted-44/fs-%2Aupdated-starter%2A-184355/

There was a voluntary emissions recall (aka campaign) that was the more likely cause of your sticker. It was just an ECU reflash and new sparkplugs tho'.