01 XJ wont start

Just wanted to know if anyone has any input. My friends 01 XJ is not running. We got it started and it idle for a bit until we gave it gas. As soon as any gas was giving it would shake and die. The engine light is flashing so I know a code is been sent to the computer, but I have no way to read it right now. After the XJ died is would not start again but the starter was turning over. Battery was good, all relays/fuses were good. Fuel pump was pumping fuel. It sounded like it wanted to turn over but something was stopping it. Anyone have an ideas.
Thanks in advance.

Hi there this is my first post. Mine did the same thing and it was the crank shaft position sensor. oh by the way mines a 95 stick if that makes any difference. Good luck! also on jeep speed theres a method described for reading codes, dont know if it works never used it.

Thanks.
It was the sensor next to the crankshaft positioning sensor. It got moved a little during an oil change. Just moved it back to the clean spot and she fired right up.