The upstream O2 sensor weld broke free from the exhaust manifold. At the time, the car was running fine - just extremely loud due to the 1" diameter hole where the O2 sensor was supposed to be attached to the exhaust manifold. I removed all parts to allow for removal of the exhaust manifold from the vehicle (serpentine belt, alternator etc.). Now that the car is all back together it will not start.

It seems to not be getting gas. It turns over real strong but just keeps trying to start. The tank was nearly empty when it was placed on jack stands - and it has also been 0 degrees here for the last week as it has been sitting. The other day, thinking that it was not getting gas, we pushed it off of the ramps added a gallon of gas to the tank - but it still won't start. I'm wondering if there wasn't a little bit of moisture in the tank to allow the gas line to freeze or ???

Does anyone have any good ideas on where and how to start to troubleshoot. I was thinking of trying to give it a shot of starting fluid, but I've never had to do that to a non-carb vehicle.

I would double check all of your sensors you've disconnected and make sure they're connected. Also, reset your ECU by disconnecting your battery for a few minutes and reconnecting it.

Thanks for the help.

Update: I double checked everything in the immediate area to make sure that I didn't know something off...but it doesn't look like it. Then I checked to see if there was any spark...it's getting spark. However, I am not getting fuel. The fuel pump runs, but I'm not getting fuel to the injectors. I guess I will keep looking.

Turns out that it was a frozen fuel line