Camshaft position sensor fault codes can be set due to a sticking / dirty VANOS solenoid. The easiest way to check it is to remove the VANOS solenoids and gently clean them with air. Reinstall and recheck. There is a software update for the ECM to address this problem in the future. The update provides a routine for the engine / VANOS solenoids to flush out debris.
If you get a fault pertaining to one specific cam sensor, (exhaust or intake) remove and swap locations of the VANOS solenoids, (they are interchangeable). If the fault follows the solenoid replace it.
Possible fault codes you may have if this is your problem:
- 2A9A Cam sensor, inlet signal - signal invalid for synchronization
- 2A98 - p0016 Crankshaft-inlet camshaft, correlation - Value outside reference range
- 2A82 VANOS intake - stiff, jammed mechanically
- 2A9B Cam sensor, exhaust signal - signal invalid for synchronization
- 2A99 - p0017 Crankshaft - exhaust camshaft, correlation - Value outside reference range
- 2A87 VANOS exhaust - stiff, jammed mechanically