i have a new battery (less than a year old) and and brand new alternator
but for some reason my car die almost every time i turn it off immediately
as i drive, the if i am not on the throttle my battery meter will drop!
i even turn everything off ( radar detector, radio, lights, a/c, everything)

i think it may be my spark plugs or/and spark plug wires

let me know what u guys think

but the way its and automatic

 

CHeck the connections on the alternator, if it's good then take it back and get a replacement

 

it was doin it before i put the new alternator on
so i dont think is it

 

Check all of your grounds. That has been the problem everytime someone has had any charging issue similar to yours. Check and double check and clean them.

 

what kind of battery/ alternator?

corrosion? grounds?

 

grounds do u mean like around my spark plugs and wires ? where?

 

Chase the ground from your battery to you frame or block which ever it goes to. Then there should be one from your block to the body. Make sure they are all clea. Check all your wires and make sure there isn't anything broken.

P.S. In your sig, Readar detector is "Radar Detector"