cold weather=car died. Need help!

[///M42 sport]

so its in the 20s here in Michigan. my 318is engine starts and I notice the dash lights flash on/off. I don't think anything of it. I drive for 20 mins. All of the sudden my check engine light comes on, lights go off, but engine is still going. When I get to the house I turn off the car and restart it thinking it could be a glitch. I notice that when I have my lights on, the check engine light comes on. When the lights are off, engine light goes off. Could it be the alternator? Battery? I have HID's. Also I'm out of town right now which sucks even more.

[///M42 sport]

Could these symptoms be from a bad voltage regulator?

[Eurospec]

Signs of a weak battery perhaps.

[accident]

Signs of a weak battery perhaps.

+1

My car started acting funny when the battery was close to death. I didnt think anything of it, though I wish I had. When I bought it it had an alarm and I had no remote for it. The battery finally died at a gas station. I bet that was a funny sight, big white guy with the underdash of an e30 cracked open ripping out alarm components. :D

[theox69]

My battery is dead every time i try to turn my car on...
Which is why I now keep a booster in my trunk. It works really well, but it's still a pain in the ass.
Thank God it's going into storage for the winter within the next week...

[///M42 sport]

It turned out not to be the battery. I found that out after having to get a 60mile tow home. :(

[Keanan]

What was it then if it wasn't the battery? A loose connection somewhere? Please don't tell me it was the driver.

[smcdermott326]

Sounds like an alternator to me

[BrewCity11]

Sounds like an alternator to me

x2. Battery shouldn't matter. You can unplug the battery after the car starts and it should run off the alternator. Guessing your alternator was crapping out and you battery couldn't keep the car running any longer.