new guy need help

[sandman_e1ka]

hi,
ive been reading alot of threads here since last year. and helped me alot in my car.
i have a 94 318is manual. I am having some problem with the electrical.. i was doing some works on my car and the radio was on. when i finish, my battery is also finish. i borrowed a battery from my freind and the car starts! i went to buy some new battery. got it fixed and the car is normal again.
i woke up the next day, went to work, and the car is perfectly starting and runnig beautifully as usual. i went for a meeting, drove in traffic, got hungry, stop and got some grub. came back to car. the car is not starting!!!!!! no cranks what so ever. check the battery. its all good. called my mechanic, went there and he was baffled!!! for the first time, he has no explanation... he just towed the car and said that he will check it with the computer...

can anyone help me out there!!!

[Gator]

This started with the battery and is most likely still a battery problem. You said you tested your battery, but unless you load tested it you can't be sure it's good. Step one replace the battery (temporarily) with a known good one from another car or for a second choice take the battery back to where you got it and have them load test it or replace it. Just because it's new doesn't mean it's a good battery. It could have an intermittent internal short.
You could also try jump starting your car. If it starts it's the battery.
Make sure that your battery terminals are not corroded.
You could also have a bad ground connection where the negative terminal connects to the engine block or frame. An easy check for this it to connect a jumper cable to the negative battery terminal and the other end to some bare metal on the car. If the car starts, you have a bad ground.
Don't spend time and money on other possibilities until you've tried a different battery.

[DesmoBob]

check your fuses. a blown fuse can help you pinpoint a problem.
check your charging system. you can buy a new battery every day but they will all die if it's not charging. with the car running, use a volt meter directly on the the battery. the voltage should be around 14-14.5 volts. if it is below 13 with the car running, your charging system is weak or dying.

[thekid]

is your alternator alright? If you replaced the battery, I would check and make sure it's getting recharged...

edit: damn, didn't read desmo's post entirely... we're saying the same thing.

[sandman_e1ka]

thanks guys,
when i change the battery, the guy check everything before installing a new 1. everything is ok. alternator and starter are good. fuse are all ok. when he installed the new, he check if its charging and what is the current volt when the ingine is running and starting.

Is there another fuse box besides the one on the engine comparment?

[jllphan]

no. glad you got 'er fixed.