hello please help, my 1994 xj40 will not start,this is what happend, i was leaveing work got into my car started it up it started first time like allways,i drove about 20ft then stoped the car turnd of the engine because i had forgot something,got back into the car turnd the key the engine just turned over would not start, i checked to see if there was a spark at the plugs there was,that was about 5 days ago the car is still at work please help