I have a 2008 Sentra 2.0 CVT that won't start even after replacing the battery. I can hear the engine noise when I turn the key but no matter how many times I try, it still won't start.
From what I've read online, I think it's either the alternator, spark plugs, or fuel pump. Here are some more details on what happened:

A few days ago, the car went into limp mode as I was climbing a bridge. I then pulled into an exit and after waiting a bit to let the car cool down, it took a few tries to start the car again.
After starting the car up, I drove home at about 25-30mph as the car was "locked" in a low gear, which I assume is limp mode. The next day, the car wouldn't start at all, even after trying to jump start and replace the battery.

This car has always had a bit of an issue with fuel economy + misfiring + acceleration, so I'm thinking it's spark plugs or fuel pump. The mechanic also told me it could be the crank sensor? I was wondering if anyone has had a similar situation. Any advice would be appreciated. Thank you!

 

The limp mode suggests there may have been an engine management issue, which could relate to the crankshaft position sensor. If that sensor fails, it can prevent the engine from starting. Additionally, problems with spark plugs or the fuel pump could definitely contribute to https://tropical-casino.com/ misfiring and starting issues.