I have a 1999 ford windstar 3.8L, that will not start. it ran fine until the other morning. When it was started it was knocking, pinging making a heck of a rattle. Was shut off after 5 -10 seconds, left it for a few minutes and tried it again, same thing happened ! I left it until returning from work that afternoon and tried it again and it turned over fine but will not start. I have checked for spark, have that, ckecked and tested the CKP sensor, the CMP sensor, the ignition coil pack and the wiring and connections. All of these seem to be fine. I am wondering if the PCM has given up ? A neighbour question weather the timing chain may have jumped making it out of time ? any idea how I would check for that, or any other ideas of what I should check ?