Do-It-Yourself information for the modifications I've completed

Do-It-Yourself information for essential wear and tear items

Articles covering all the ways to maintain your car

All about the BMW 330ci

Various links that I've found valuable

A few pictures of my car and some others

Changing Your Battery

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Changing your battery is really quite simple. As long as you can lift the battery, you can do this DIY in just a matter of minutes.

When is your battery dead?
Batteries have a designed lifetime of 5-6 years. My original battery lasted for 6 years before it died once it started getting cold out. One sure sign is that as it gets colder, your car will take longer to start and hesitate. Finally it will flat out just not start. That is when I knew for sure that mine had bit the dust. If you do replace your battery and a few days later, the same thing happens, then it is your alternator. You can also take your old battery to the local auto parts store and have them determine if your battery does indeed need replacing. Either way, it's going to die eventually. Make sure that you recycle your old battery appropriately.

Battery Choice
I chose to go with an inexpensive alternative battery instead of the OEM battery. One of the major reasons behind it was that it was a Sunday night and I needed to drive my car to work the next day. Also it's much cheaper. The Duralast 49-DL is an excellent alternative that I will highly recommend to anyone shopping for a battery. Just stop by any local Autozone and you can pick it up. The sales person will not want to sell it to you since it isn't "designed" for the 330, but trust me that it will fit and work just fine. Below are some specs to show the difference between the OEM and the Duralast battery for those of you who are wondering.

  Cold Cranking Amps Cranking Amps @ 32F
OEM Battery 640 765
Duralast 49-DL 850 1000

Tools Needed
Large phillips and standard screwdrivers
Socket Set

Parts Needed
1 49-DL Duralast Battery ($80 with a $12 core charge that is refunded when you return your original battery)

Warning! Carefully follow the directions for removal of the battery terminals. The positive terminal is disconnected last and reconnected first. Failure to follow these directions may lead to sparking and/or shocks. Be careful not to short the terminals together.


The new battery

Locate the battery cover

Battery cover removed

Remove the battery cover in the trunk
1. Open the trunk and prop up the bottom of the trunk lining. (The tab that you use to lift it up will attach to the trunk lining at the top.)
2. Using a standard screwdriver undo the two screws holding down the cover.
3. Remove the battery cover. This will involve pulling the lining of the trunk out of the back lip of the cover. Grab by the green emergency gas cap opener and it will pop out. Then wiggle the cover out of the way and set it aside. It will come out, just use some patients.


Remove the negative and then the positive terminal

Remove the battery making sure to remove the vent hose

Remove the white block

Remove the old battery (Negative then Positive)
4. Using a 10mm socket, loosen the negative terminal on the battery (black wire) and disconnect it.
5. Next loosen the 10mm nut holding the positive terminal down and remove that.
6. Now using a 1/2" socket, remove the two bolts on the bracket holding the batter down. Once they are removed push on the black metal support behind the battery to take off the bracket. Once the bracket is removed, set it aside.
7. Locate the vent tubing for the old battery and remove it from the white plastic tubing attached to the car.
8. Using a screwdriver or other prying tool, remove the white plastic block that was used to position the old battery. We are now ready to reinstall the new battery.


Reinstall the positive terminal cover

Reattach the vent tube with the supplied adapter

All done

Install the new battery (Positive then Negative)
9. Take the red cover off of the old battery (being careful not to damage it) and reinstall it onto the new battery. Also install the tubing that came with it as shown in the picture with the tubing heading off to the left.
10. Place the new battery into the battery well.
11. Reattach the positive terminal and tighten the 10mm nut down. Lower the cover to protect the terminal.
12. Reattach the negative terminal and tighten its 10mm nut down.
13. Using the male to male adapter, put the small end into the white tube and the large end onto the new tube until they meet. This will ensure that the gasses produced by the battery will vent properly.
14. Reinstall the battery bracket and tighten the 1/2" nuts. I placed some wrapped tape to add some height to the battery and then tightened it down with a large phillips screwdriver.
15. Replace the battery cover and put everything back together.
16. Revive your car.



Upon completion you will need to reset your clock (your trip odometer, MPG, and MPH OBC features will be reset as well) and fire up the car. Mine started right away and haven't had any problems since. An excellent alternative that will save you about $100. Happy motoring!



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