CAM Position Sensor

I have a 2002 Audi A4 and the MIL comes on intermittently (may be off for a week, then come on for a day, then go off for a day and come on for a week, etc). My OBDII reader shows code P0348, which a quick internet search reveals as “CAM Position Sensor A Ckt High Input Bank 2”. The car runs fine, mileage is not suffering, no noticeable effects other than a slight shudder in the engine every few weeks that causes the light to come on again. Is this a serious problem? Is it expensive to fix? Do I need to fix it? I appreciate any help.

Check the wiring and connector to the sensor for corrosion or loose contacts.