Ok, really need some help with this one. I'm driving my 06 Cobalt SS/SC through town the other day and the battery light comes on, no big deal right? Head to the auto parts store to get my battery checked, on the way the car dies and will not start acts like the battery is dead. So I call a friend and we go and test the battery at Auto Zone, battery tests bad so I buy a new battery get back to the car and put it on. Car starts right up and I'm on my way back home, about 10 min. later the check engine light starts flashing and the car starts running like crap!! ( A steady flashing CEL signals a miss fire correct?) Battery light comes on again and so now I'm thinking ok it must be the alternator. Get the car home and order a alternator, put it on last night and tried driving it and it is still running like it has a miss. It has not thrown a code, and on my AEM Uego the afr starts out at 14.5 and then immediately goes down to 10.0 and stays there. My car has around 140,000 miles on it and for the life of me I don't understand what is wrong here. Also when I am driving it the check engine light will flash but not the usual length of time that it would to show a miss fire, it flashes just quick enough that you can notice it. PLEASE SOMEONE HELP!!!!!!

 

Check ure voltage.

 

ok voltage at battery without the car running is 11.98V, while car is running the voltage started out at 14.3V stayed there for about 20 seconds then would bounce from 12.2V to 14.1V. Is there a seperate voltage regulator that is not on the alternator?

 

I agree with Chevycobaltss3. Check your alternator. It is probably just not putting out enough power to run everything and recharge your battery. Everything worked fine since you put in a new battery with a full charge, well until the charge ran out.

how many amps is it putting out?