Dead battery again? Oh noes!!

[Cybspur]

Well, I believe I posted a month back about having bad luck with Autolite batteries in this MN winter. Anyways, I got my fourth Autolite battery, under warranty, about a month ago, because my third one died. Well, seeing as its been on average -20 here in MN the last couple of nights, I knew I was going to have a problem. I went to go start my car up yesterday morning to no avail. Well, I got tired of exchanging these batteries so I brought it inside to thaw....I put it back in the Pro5 this morning and my car starts! Hip hip hooray!! I let it warm up for about 10mins then I give it a short drive around the block. I come back in to get my daughter ready for school. It takes maybe about another 20mins, so we head out to the car. I turn the key, the car turns over but doesn't catch. I do this a few times, and then I see the temp shoot up to hot, every time I crank it. Long story short, anyone have any ideas whats wrong with my Pro5 this time?
Thanks for the help guys.

 

[P-Funk!]

Bad ground! Check bat to block, bat to body!

Also, put an ammeter and test for a current leak when the key is off.

 

[wiprotege5]

If your temperature gauge is shooting up to Hot, I think you need to replace your thermostat.

 

[slavrenz]

Maybe you've got some kind of bad wiring with your ECT sensor that is causing your battery to drain? That's a weird problem.

 

[Cybspur]

Well, what do you know? My car starts and works again. Strange. I was just gonna take my battery to go get it checked, and I decided to see if it'll start.
Hmmm, can anyone narrow it down to about a 10,000ft view now?
Any suggestions welcomed, as its gonna be a cold weekend to be working on my car, and I'd like to get it done as quick as possible.

 

[pasadena_commut]

Hmmm, can anyone narrow it down to about a 10,000ft view now?

It's around 80 today here in LA, so we don't actually have this particular problem, still...

CCA is measured at 0 degrees F, you are exposing that battery to -20 F, and the electrochemistry pretty much grinds to a halt at that temperature, assuming that the electrolyte is even still fluid. If the inside of your battery is a big chunk of ice you can imagine why it might not work.

The best solution: heated garage.
Cheapest but most labor intensive solution: bring the battery into the house for the night.
Other options: block heater

Otherwise, shop around for something like a Champion Subzero battery, which has been designed to work better at lower temperatures than the average battery.

Ask a mechanic in your area what he would do. It sounds like the battery store guys just want to keep selling you batteries.

Also, this table might also indicate what the problem is:

http://www.jgdarden.com/batteryfaq/carfaq4.htm#freeze_points

 

[Juleehen]

On my old mazda, when my alternator strap broke, the car stoped cooling itself and the RPMs where going all over the place when i was on idle. Maybe the strap is loose and it dosn't catch when the car is cold.

I don't know much about car troubleshooting but i think it might be similar, espacially if you keep having dead batteries.

Good luck


P.S. I had to change my car battery at -25 in the dark last night...i feel your pain about working on the car outside !!!

 

[Olestra]

...
CCA is measured at 0 degrees F, you are exposing that battery to -20 F, and the electrochemistry pretty much grinds to a halt at that temperature, assuming that the electrolyte is even still fluid. If the inside of your battery is a big chunk of ice you can imagine why it might not work.

The best solution: heated garage.
Cheapest but most labor intensive solution: bring the battery into the house for the night.
Other options: block heater
...

Assuming that's a battery warmer you're talking about? A block heater would warm your engine and coolant but your battery would still freeze...

 

[The Short Bus]

Can't suggest anything else to try than what was already mentioned, but my P5 has been going through the exact same weather as yours. I put in a Duralast Gold battery this summer and there hasn't been a time where it hasn't started. No heated garage either.

 

[wiprotege5]

Well, if we're talking about cold weather batteries,

Optima red top.

When my car had to sit out, I replaced the stock battery with the optima and never had a problem in any weather starting my car.

 

[P-Funk!]

For extreme cold weather. Turn your headlights on (bright) for 30 seconds. Turn off. Start car. This warms the battery and gains more power than you lose with the lights. If it still won't crank - it would not have started anyway. The battery is getting old.