Pontiac Firebird Sputtering PLEASE HELP?

I have a 99 pontiac firebird and last week one night the check gages light and the ABS INOP light both came on. I think the check gages was light
was on for the battery because that one was was waving back and forth alot. Nothing happened that night I didn't notice anything wrong at all. Then the next morning it wouldn't start. I jumpstarted it later on in the day and it had been working fine until today. Both lights came back on and it started sputtering for about a quarter of a mile. I didn't have to much control over it. It seemed like when I went upwards on hill or whatever it lost all power. I took it into an auto repair place and they thought it was something with the alternator so they fixed that but on my way home it broke down again. I am sorry I don't know anything about cars so any advice would be greatly appreciated. Thank You.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Take it back to the shop who replaced the alternator. They should fix it properly.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
but do you have any idea what could be wrong with it.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Sounds like an alternator of battery. You said they 'fixed' your alternator. Did they replace it?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
This is going to be incredibly easy for somebody who knows something about cars. We can't really troubleshoot here by ASCII. Find somebody where you are that can fix things.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.