I had this experience with as 2006 5AT TL, but here's a general question about batteries and battery drain:

I'm wondering if its possible that excessive battery drain can occur if I am warming up the car for a prolonged period of time, say 15-20 minutes with full heat, heated seat (low), front/rear defog/defrost, mirrors, etc. while I scrape off snow and ice from a recent cold snap/storm. Since the car isn't moving during this time, does the battery get less of a charge? Once warmed up, I probably only do about 10-15 minutes of city driving before parking, so am thinking there isn't much charging going on. I recently had a 4.5 year old battery all of a sudden give out and am curious if this may have contributed to it's sudden demise, even though it was due for replacement.

Thanks in advance for any thoughts!

 

Rear defroster is on a timer... Most are 10 minutes so I do not think you have much to worry about there. Warming up your car like that is BAD for it as it spends a much longer time running rich... The best way to warm up your car is to turn it on, clear the windows/snow off and then get in and drive away gently. loading up the engine will cause it to warm up much faster. if you do not need to clear off your windows/snow just wait a minute and then drive away gently.

 

Unless your alternator is not working properly , you should be fine

 

no, the battery was old. 4.5 years is a long time!

 

Thanks for your input. I agree the battery was shot, and know that long warmups are probably not good, but it actually takes that long for the windshield to clear enough to see through! Same for every car I've owned, maybe it's just the humidity around here. We usually have to plan for an extra 15 minutes when leaving the house. If it's bad for the car, I don't see any way around it.

However, to restate to my original question, assuming the alternator is functioning properly: is the quality of charge to the battery during a long fast drive the same as when it's sitting idle?
I'm just really curious!

 

Explain to me/us in what way is it bad? modern cars only run rich until the cats are heated (very quickly i might add, want proof, get a live data reader and monitor your car/cats readiness state). People tout this all the time with little to no explanation/proof, but id like to know what will go wrong with the car, with Proof. Every car i have ever owned gets warmed up while i clean it off then usually the driveway. Once im in it i go to work, where3 the car runs all day, much of the time idling. In the 1.5 million+ miles i have accumulated on my vehicles i have never had a motor issue, or any other issue that could be attributed to excessive idling. And that is also on 15-20k oil change intervals

I can tell you on average, shutting the car off as much as i would have to during the day, would be harder on the motor/bearings, oil, starter than just letting it run.

 

Go read your owner's manual and get back to me.... Not one of them says to let the car idle to warm up and yes the car runs rich until the engine heats up sufficiently All the car does when the O2 sensors warm up is switch from open to closed loop....

Straight from the last Acura manual that I had

A cold engine uses more fuel than a
warm engine. It is not necessary to
‘‘warm-up’’ a cold engine by letting it
idle for a long time. You can drive
away in about a minute, no matter
how cold it is outside. The engine
will warm up faster, and you get
better fuel economy. To cut down on
the number of ‘‘cold starts,’’ try to
combine several short trips into one