everyday i turn the car on it will barely turn on. once is on the abs,slip and vdc lights are on. but they turn off in seconds. it feels like if the battery was dying but its not. everytime i turn my lowbeams the dash lights get dim and the gas pedal wont accelerate, if i turn anything rlse like my a/c radio or high beams the abd vdc and slip lights would come back and feel like its going to turn off. i got the battery and alternator check and theyre good what can it be btw no CEL or any other light.. here is a video. tia

http://static.photobucket.com/player...psc9d6f0e3.mp4


20130325_223640_zpsc9d6f0e3.mp4

 

Sounds like alternator (yes I know you checked it) or grounding issue?

 

i also though it was the alternator but no. i got it check down 3 tines and its good. battery is good also. i thoigh it could be one of those cam or crank sensors but after some research theyre not. ima clean my maf and throtle body next hope is some dirt.. it happen to me once in the winter (dec) it was only once so i didnt pay attention to it. then one more time in january and now in march the whole monh been like this. i dont want to drive it like this 2 days ago i had to drive with lights off to be able to get home.

 

it could be a ground but where to start looking?

 

Are you sure your battery connections are tight? How exactly did you check your alternator? Maybe it's producing power fine, but the voltage regulator is F'd up?

 

first i took it to autozone and they test it with a voltage meter ot something like that. both the alternator and the battery. they were good. after that I use an old trick, disconnect it the negative battery cable while the car was on and it didnt shut off. i took it to another autozone and they said the same it was good. if it was the battery the battery light would come if it was a sensor the CEL would come up. i even ask them to check for any codes in case the cel light wasnt working but nothing came up..

 

hey guys i took it back to autozone to get it check out again since this last two days it been happening nore often. they tested the battery and it said it had 0% charge. check the alternator and the volts were 12-13 (when its suppost to be 14.1) and when i turn the lows,a/c,radio the meter would read 8-10 volts. the guy at autozone which wasnt very experience adivise me to get new battery and new alternator because the alternator had already damage the battery.

 

How old is your battery? I wouldn't get a new battery unless your current one is older than 3 or 4 years old. It is true that conventional automotive batteries take some abuse/damage when they are completely discharged, but if it's a newer battery and was working fine before, you don't have to replace it just because it was discharged completely one time.

 

thats what i though. battery is not that old was replace 2-3 yrs ago. im getting an alternator and see if that fixes. why wouldnt the battery light come up in the dash tho.. and alternator volts would go up from 12 to 13 and when everything was on from 8-10 slowly hope is the alternator.

 

I'm not sure what the voltage level threshold is that it needs to drop to in order for the battery/voltage warning light in the dashboard to come on. I would expect it to come on if the voltage dropped as low as 8 or 9 volts as you say, since that is way below the voltage that the battery alone should put out when the car is not even on (meaning that it's not being complimented with a live power feed from a running alternator). Most cars generally have somewhere between 12 and 13 volts from the battery alone if the battery is fully charged and healthy, and usually around 13.2 to 14.5 when the car is running. It sounds to me like it is the alternator though based on your symptoms as you describe them.

As far as the battery is concerned, if you find that your car is not cranking up in a convincing fashion on cold starts after replacing the alternator, then you might want to consider replacing the battery... although I doubt this will be the case. I had my OEM battery in my car for 8 years before replacing it, and it still started the car... just not in that convincing of a fashion. I only replaced it because I didn't want to risk getting stranded somewhere, so I think you'll be fine with a 2-3 year old battery that has been run down once. If you do notice it being significantly weaker than before though, replace it sooner rather than later because you can actually do damage to your alternator by overworking it if the battery is not really holding much of a charge.

 

thanks!

 

Just wondering if you replaced the alternator, and did it fix your problems? I just started having similar issues to yours, and I'm pretty clueless at this point. Here's my thread about my situation for those interested.

https://g35driver.com/forums/g35-cou...dead-help.html

 

yes i replaced the alternator my self and it fix the problem. it charged the battery back and felt like new. =)

 

for some reason after i would drive it for a while the alternator would work fine but as soon as i would turn on it would have real low battery..