Check Engine Light On problems of the 2008 Volkswagen Jetta

Since 2012, I have had check engine lights that no mechanic has been able to diagnose, because everything was fine when they would check the knock sensor. They would reset it, and see if it came on again. However, there would be long periods where it wouldn't come on. It has not come on, since novermber of 2014. 4/13/2015, at approximately 1900 hours, I was traveling on a major freeway, in afternoon traffic in houston. When, my engine began to die. My control panel went dead, and my engine was gradually dying, with the radio and electricity still working. I ended up being stranded in a moving lane, at a split, with vehicles wizzing from 60-80 mph. I called for a wrecker over a police radio, but 5 minutes later my vehicle restarted like everything was fine, died and restarted again on shoulder of freeway. I then got off the freeway and went parking lot to parking lot got home, took it to vw dealership first thing. Due to no engine light or fault code, dealership guessed ignition switch. Due to problems with dealership, took vehicle from them and paid for diagnostic. Discovered in report they listed malfunctioning camshaft, which they were going to try and have me pay. I had the ignition switch replaced, died on me again on 4/19/15. Because searching with my VIN did not reveal defects or investigations and my vehicle was serviced for the 1 recall -- I searched with the engine code "bpy", I found there had been an investigation and vw decided to not do a recall but "update", thus didn't have to give owners notice. However, their own mechanics seem to be unaware. I realized that the technician thought of the ignition switch due to gm being in the news after the deaths, due to similarities. Vw did an "update" to settle the investigation, did not give notice, and I would have had to pay even though they agreed to extend the warranty for 10 years and 120,000 miles.