I need help starting my car

[AnLupou]

Hi,

I have a Nissan Versa 07 Auto Trans and it's not starting anymore. I changed the battery on the car for a new one yesterday, no problem car started went for a 10 min drive to make sure the battery is charged. Three hours later i want to leave with the car, get in turn the key power shuts down completely, i give a boost still no sign of power, after checking everything i find that its the + connector of the battery that doesn't hold anymore.

Today i changed the screw on the connector with the bolt, now its solidly in place, try to start the car cranks but doesn't start, I give it a boost, same cranks but doesn't start, i put back my old battery, you know might be a bad cell, boosted it, it cranks but doesn't start. I think the car might be "drowned" so i remove the plastic cover on the engine (you know nissan build it so you cant access the spark plugs) put a radiator on it for two hour to make the fuel evaporate (it's -15C right now yesterday -40C) but it changed nothing the car just cranks but doesn't start. And it's not a hard crank or a low power one, it's the normal crank that i get when my car used to start first try. I don't know what to do anymore... If someone has any idea what could be the problem, I talked to my mechanic over the phone he can't help me without having the car in front of him.

Sincerely,

A desperate Nissan owner -_-