Recently my car has been stuttering badly and then the car shuts off. It seems to happen when it shifts gears to 30-40mph. Ive noticed when I warm up my car for a long time, it will run fine. I have changed the fuel filter and spark plugs but still stutters and shuts down. I know you should warm up your car, especially during Chicagos winters, but ive always been able to just start and go. But now i cant, and it stutters badly then car shuts off. Sometimes ill start it right back up and then it will run fine, hits 40mph and the trans seems to shift fine. I have no idea what could be wrong, as ive heard many things can be wrong. I would like a final solution before i consider trading it in or scrapping it. Thank you!

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