After extensive research, I found a post from Charles R. Dinges which said:

"The solution was to re-position the line feed to the sensor. I had for sometime felt it was a wiring problem � not a knock sensor per se. Well, I was just standing there one day (pondering) looking at the knock sensor wire and where the wire was routed and suddenly I decided to move it away from proximity of the alternator. Well since then I have done my darndest to get the check engine light to come on � without luck. Yeah! Conclusion � my problem is solved. Shielding must be the important element here, so as to prevent spurious voltage signals from interrupting the signal from the knock sensor."

I did it on my car, took it for a 15 minute drive and no cel yet. It had been coming on within 5 minutes, so I've got my fingers crossed.

Can you believe such a simple solution and the amount of hours and parts someone could throw at this problem!

Thanks again!