I have a 2008 Sebring 2.4l 2dr convertible that's been sitting for quite a while, a little more than a year. This is the first time it's been started since then. When I started it, as you can hear in the video, the engine goes way down in revs and barely comes back. The second time I started it, it did the same thing, but it went down in revs three times and on the third it just died. I can start it again, but I don't know what the issue is. The battery is very dead and I had to jump it, but I'm not sure if that's the problem. I've asked around and some people think it's the fuel (which is as old as how long the car's been sitting), some think it's the battery messing with the engine, some think it could be the alternator, and one said it could be the mass airflow sensor. What could it be? Thanks for any help. I'll try to answer questions as soon as I can.
Also, the engine won't run for me to read codes with an OBD II scanner.

 

Replace the battery to start with and you will not have any codes because the battery is dead. and FYI this car does not have a mass air flow sensor.