2006 Jetta TDI BRM 207000 miles quit running on the highway for about 1/4 mile. It restarted on its own and I continued on. Did a VCDS scan and found a code for a Cam Position Sensor Fault. How hard is it to replace this sensor. And why has it been running ever since. Is there a loose ground wire or almost broken wire somewhere. Is this a common fault on this engine. I have had the car since new. The cam has been replaced at 137,000 miles.