I have a 2002 Lancer ES. For about a month it was having trouble to start. It eventually would start but it got worse day after day until yesterday (Christmas Eve) it wouldn't start. I bought a battery and installed it. It was turning over but wouldn't start and at several tries it wanted to start and then it started and warmed up then idled just fine. When I took it for a spin it would just die when I stopped. I was able to turn the key and it started right up each time this happened. I'm not a car guy but can do only the minimal like change plugs, air filter. Does anyone know what would cause this? Thanks for your help!

 

Is the service engine light on? You may have a clogged cat.