What might be the cause of car not starting

Hello, you did not indicate which engine is in your Cobalt. That could be important information. It is impossible to know why your vehicle will now not start without performing needed testing. Either there is no fuel getting to the engine, no ignition spark or no air getting to the engine as needed. An anti-theft concern could be present, where the starting is prevented. Some kind of internal engine concern could have occurred. It's simply a guessing game until hands on testing is performed. Seek guidance at a local shop near you to assist. https://repairpal.com/auto-repair-near-me