Hi. I am about to go on a month long vacation, should I use a trickle charger to maintain my battery? Thanks.
yes! It is not worth the headaches of a depleted battery that may never fully recover. I have two, one for an e46 330i and one for an M Roadster (Z4). it is a great tool to keep these cars happy in long or short term 'time out'
For only one month I wouldn't bother doing anything and you will most likely be just fine. I have left my MINI Cooper for up to three weeks, outside and it starts right up with no problems. If you want to be on the safe side you could disconnect the battery, which is what I do with my older BMW that sits for longer periods.
It depends highly on the current state of charge in the battery. If it's fresh, yeah it may hold out for a month, but will no doubt be weakened. And that is no good. Disconnect the battery on a modern BMW, for only four weeks? (Winter storage.....m a y b e, but only with some guidance from a tech) Not to mention, an M3? I don't think that is recommended. You could be opening yourself up to a myriad of other issues if the microprocessors inside power down. I am not an 'expert' but this is not the conservative approach IMO. Too many risks involved, disconnecting and reconnecting a powerful battery for a four week trip.... Don't mean to come down hard on ya here, but think about it..... I think BMW knows that its customers may have their prized cars sitting for a while and in their wisdom provided an easy pragmatic solution.... the BMW battery tender.
A strong driver in the life of a lead-acid storage battery is the degree of sulfation of the plates. That is an irreversible chemical change that reduces the battery's capacity. Sulfation occurs when the specific gravity of the electrolite falls below 1.225 (12.4v or 75% charge). A BMW, like many modern vehicles has some electronics that are powered up all time, resulting in what is usually referred to as parasitic draw. On a BMW the normal parasitic draw is in the 30-60ma range. While that won't pull the battery below the point where sulfation begins in a short period of time, longer parked periods can result in the battery dropping below the 75% charge point. Any time that you know the car will be idle for a week or more and it will be parked where there is 110VAC power, connecting a battery tender is recommended and will help with battery life.
Well-said, jlevie. An alternate source for the same device BMW sells is available here: http://www.batterytender.com/
cold start problems HI friends... i have a 2001bmw 318i.... it cant idle in the morning when its cold, and it cant reach speeds of 170 km/hr. what could be the problem?::
cold start problems HI friends... i have a 2001bmw 318i.... it cant idle in the morning when its cold, and it cant reach speeds of 170 km/hr. what could be the problem?::
trickle chargers if you use one, don't use a cheap one. Overcharging a battery is bad for it too. For the 2001 318 that won't idle when cold, it could be tons of stuff, for the top speed, maybe it's an issue on displacement! anyway, there isn't enough to go on there. Matt
Battery tenders You can save a few bucks and achieve the same results with Harley Davidson battery tenders. I bought 8 on sale and have everything from Z-06 Corvettes, Roush supercharged Mustangs, SRT Challengers and street rods along with our Mini and M5. Never a failure or a battery go dry.
