So I was driving down the road yesterday, and my radio cut out, i then lost cruise control, shortly after, my jeep started making a strange thumping noise, almost like a misfire, so I pulled into a gas station and a I stopped my idle started going down pretty low and then cut out. Had it towed to my house then took out the alternator to get it tested, and of course it was bad. Got a new one installed it, then tried cranking the motor. It will turn over, but cuts immediately, when I give it gas it will stay on, but as soon a I let off it dies, any ideas? Thanks

 

What year?? Details, details. We need more info.....

 

CEL?
Codes?

 

If the alternator was bad, it wasn't charging your battery.

And with a low battery, stalling is a primary symptom.

Always best to completely charge a low battery with a battery charger, not the alternator, which is designed for "keeping" a battery charged.

See if that resolves the issues.

 

99 4.0 luckily I had an extra battery laying around so I tossed that in, still didn't solve it, I read on another thread that turning the key but not starting it for a few seconds then cranking it can fix it, tried that and it runs fine now