alternator battery problems

changed alternator got new battery car now will start but wont stay running seems like still just running on battery power like the alternator isnt chargin battery while its runnin it will start but wont stay running want to know some cheap easy ways to figure out problem and maybe fix not very smart when it comes to cars so a lot of help is probably needed thanks

Could be a bad connection to the battery, bad coil pacs, bad wires... a few different possibilites. Maybe even fuel delivery related...

changed alternator got new battery car now will start but wont stay running seems like still just running on battery power like the alternator isnt chargin battery while its runnin it will start but wont stay running want to know some cheap easy ways to figure out problem and maybe fix not very smart when it comes to cars so a lot of help is probably needed thanks

Does the Battery light on the dash come on? If not, then when the motor is idling is it like it's going to cut-out similar to a carb'd motor would if you let the choke in too early? If so then IAC vlave or even EGR but more likely IAC. If it's not like that and it suddenly stops then I would say a bad sconnection somewhere. Did you clean the battery connections when you switched the battery, have you checked the alternator is installed 100% correctly and have you taken a reading for it's output?