my E70 won't start eeeeek

[michaeljr6]

In the morning usually or cold, my car would take a few tries for it to turn over and start. I brought it in to get it fixed last week, however they told me it was b/c of my aftermarket subwoofers. so then i had to pay $9XX, they told me they replaced the battery and some overly expensive wire.

after taking my car home yesterday, this morning the problem has arisen again. it seemed that they never did fixed anything and replaced something that wasn't bad in the first place. could it be the starter or something else? so now my car has no subwoofers now and it still struggles to turn over in the cold mornings.

what should i do?



****UPDATE****
The problem was actually the fuel pump and not the battery/wire. This will be covered by warranty. However you can use me as an example of what happen if you install something (aftermarket stereo) and BMW will use it against you to void warranty.