Stalling problem with my 03 Chevy Tracker?

[Tracker0374]

My Tracker stalls on the highway then after about 15 to 20 minutes it restarts. Computer is throwing no codes. GM mechanic cannot get it recreate the stall and cannot diagnose the problem. I have done some research and found that trackers had a problem with the camshaft position sensor, the sensor gets hot and mis reads time causing the engine to stall, once it cools down it starts reading time correctly and the engine starts and runs fine. Have you heard of this problem before? And how difficult is it to time this sensor? Since the engine has no ignition wires how do you put a timing light on it?