Help: 96 XJ Engine Shut off while driving
 

So this happened twice before today, and it got started right away. and everything was fine, until today.

Model: 96 XJ, 4.0L

Symptoms:
1) I was driving, and the engine shut off, steering goes numb. brake still works. so I was able to slide on the side of the road and stop the car.

2)Then, I switch to Park from Drive, and it won't start no matter what.

3) I was able to start again, in Drive. But i can only get it started without my foot on the brake.

4) After the engine goes back on, as soon as i give it a little gas, the engine shuts off again.

I was about 1/2 mile from home so I tripped home, with engine shutting down about 5 times.

Just when I was about to parallel parking into the drive way, it shuts down AGAIN, leaving the car in the middle of the street.

And this, time no matter what I do, it won't start.. I had to wait for 2 mins, and restart the car by the method above. And then, without driving any further, I put it in park, and turned off the engine.. Finally, I restart the car as normal, and it drives fine again..

Extra Info:
Before this happened, I 2 errors that is causing the check engine light to go on and off. Then I noticed the temperature gauge is not working. Auto Zone told me they are caused by coolant sensor, and Neutral Safety Switch(NSS). But I thought the NSS won't engage after you start the car… so please explain more if you think NSS caused this.

Check NSS. Your ground too from battery.