[netsurfr1]

I recently bought a 2008 335i e93 that won't be driven during winter. My plan is to park it in a heated garage over the winter months. There are no AC outlets available so I am not able to use a battery tender so was hoping I could simply disconnect the battery but BMW dealer advised against that saying that disconnecting the battery for long periods of time could screw up some of the electronic modules in the car. Is this true and if so what other options do I have?

[neilvan]

I do this every year 3 miata's and my 335/530 switching out summer and winter. Remove the battery and charge it now and then while its out, reinstall and go.

I mean you lose your mileage check and radio resets but that's about it?

[Emilime75]

I've had my battery disconnected for 6 months and had zero issues when reconnected. With that said, others have reported problems after doing similar.

[AllBlackBimmer]

You have a heated garage, but no outlets? No even with an extension cord?
For $50 you could have a battery tender, which is well worth it.

Some people have had issues with have the battery disconnected for long periods of time, and others haven't... i use a battery tender so I dont have this issue

[Efthreeoh]

Is there a light fixture in the garage?

[netsurfr1]

No outlets accessible because this is a large complex underground garage so guessing landlord doesn't expose AC outlets since there's no way to meter electric to individual residents so they block all outlets.

Originally Posted by Efthreeoh

Is there a light fixture in the garage?

[netsurfr1]

Anyone have any ideas why some bmw have problems and some don't when the battery is disconnected for long periods of time? Mine is a 2008 e93 with Nav/idrive if that matters...

[Emilime75]

Will you not be in the city where the car is being stored? Can you take it out on dry days to keep the battery charged, fluids circulated, bushings flexed...?

[netsurfr1]

Yes our house is only 10 minutes away from where it will be kept but I was planning on prepping the car for storage (fuel stabilizer, high psi, car cover, etc) and not driving it at all due to snow/salt but maybe I need to consider driving it for 20-30 minutes periodically when there's no snow/salt on the roads but how long can the battery last when not driven regularly before it dies?

Originally Posted by Emilime75

Will you not be in the city where the car is being stored? Can you take it out on dry days to keep the battery charged, fluids circulated, bushings flexed...?

[freakystyly]

You could probably idle it for a half hour/hour if safe to do so, once a month. As long as you don't sit inside under the cover and have a nap... It sounds crappy tho for the environment. That's not as effective as driving but better than nothing and gets some of the car juices flowing.

Had a buddy do that with his 135 and it was fine, aside from an intake squirrel nest and some chewed wires.

[Emilime75]

How long the battery will last depends on the battery, really, and its condition when the car is parked. A fresh, new battery "should" last longer than an aged one...at the same time, cold temperatures aren't good for batteries holding a charge for long periods of time.

[rick100]

Originally Posted by netsurfr1

Yes our house is only 10 minutes away from where it will be kept but I was planning on prepping the car for storage (fuel stabilizer, high psi, car cover, etc) and not driving it at all due to snow/salt but maybe I need to consider driving it for 20-30 minutes periodically when there's no snow/salt on the roads but how long can the battery last when not driven regularly before it dies?

If this is a large underground complex , which I supposed is a just a fancy name for an underground garage. Why not just go once a week or once every two weeks and drive the car in the underground complex?? ...

how long is winter? 4 months? ... Even in Canada , the only 2-3 months of snow are mid dec, jan , feb , mid march. Not much snow coming after that .

Even starting the car once in a while should be good enough .

If I had to park the car for the winter, and I was doing it in a place that I can not possibly drive it until summer come , sure I ll go ahead with a proper winter prep. But you actually have an " underground complex" , I ll be driving my car there just to keep fluids running , battery charge, brakes working , suspension working.

I just had my winter car park in my house for 3 months because my steering wheel pump broke and I was too cheap to fix i t . I wished I fixed the car before, now my brakes are all messed up , the car drives like crap. Cars dont like seating around

[netsurfr1]

Yes this is a large underground parking for a large condo complex but not large enough to drive around in it long enough to get the oil hot enough to burn off the water from combustion but maybe I should just plan on driving it once every 3-4 weeks when we have a "nice" day with no snow/salt on the roads. Our winter season is really late Dec to early Mar so not long. Would really prefer to park it for the season but with no access to AC outlets for a battery tenderer I'm afraid to remove the battery and run into electrical problems when I reconnect it.

Originally Posted by rick100

If this is a large underground complex , which I supposed is a just a fancy name for an underground garage. Why not just go once a week or once every two weeks and drive the car in the underground complex?? ...

how long is winter? 4 months? ... Even in Canada , the only 2-3 months of snow are mid dec, jan , feb , mid march. Not much snow coming after that .

Even starting the car once in a while should be good enough .

If I had to park the car for the winter, and I was doing it in a place that I can not possibly drive it until summer come , sure I ll go ahead with a proper winter prep. But you actually have an " underground complex" , I ll be driving my car there just to keep fluids running , battery charge, brakes working , suspension working.

I just had my winter car park in my house for 3 months because my steering wheel pump broke and I was too cheap to fix i t . I wished I fixed the car before, now my brakes are all messed up , the car drives like crap. Cars dont like seating around

[pedro2u]

I've pulled the battery for 3 winters from my e46 ZHP vert, and my most recent hibernator '08 E92 which I stored last winter also without the battery. Storage is unheated

I keep the batteries on the shelf in my basement (55 degrees) and give them a charge just before I reinstall them and take the cars out of storage in the spring. No issues whatsoever with either car.....

[SpeedBuggy]

Be sure to get some mouse repellent, little buggers like to chew wires. Peppermint oil or liquid works well. I use a mouse repellent that's is a small peppermint pad in a plastic pack. One under the hood, one in the interior. I spray some liquid in a small medicine cup similar to the one you get with NyQuil and place on the garage floor near the tires. Purchase on Amazon.

Also make sure you cover or wrap something around the tailpipe, they like to make nests there also.

[netsurfr1]

Great to hear as this is what I would prefer to do with my 80 e93. Still worries me that the dealer & some owners warn about electronic modules problems when disconnecting the battery for long periods of time.

Originally Posted by pedro2u

I've pulled the battery for 3 winters from my e46 ZHP vert, and my most recent hibernator '08 E92 which I stored last winter also without the battery. Storage is unheated

I keep the batteries on the shelf in my basement (55 degrees) and give them a charge just before I reinstall them and take the cars out of storage in the spring. No issues whatsoever with either car.....

[netsurfr1]

Thanks. Great tips.

Originally Posted by SpeedBuggy

Be sure to get some mouse repellent, little buggers like to chew wires. Peppermint oil or liquid works well. I use a mouse repellent that's is a small peppermint pad in a plastic pack. One under the hood, one in the interior. I spray some liquid in a small medicine cup similar to the one you get with NyQuil and place on the garage floor near the tires. Purchase on Amazon.

Also make sure you cover or wrap something around the tailpipe, they like to make nests there also.

[netsurfr1]

Curious if one of these battery generators would have enough juice to run a battery tender even if the battery pack has to be charged periodically?

https://www.amazon.com/dp/B07SM5HBK1...J0QD2JHH&psc=1