'14 GLK cam sensor question
 

Should these be a preventive maintenance replacement type sensor? Reason I ask is I was reading somewhere where there were "wicking" issues associated with them that cause a more expensive to repair problem. Looking at wiring to sensor I'm not so sure. Obviously if one goes bad it should show up on the diagnostics. Seems the local dealer keeps them in stock which tells me they do go bad.

I just replaced the serpentine belt, tensioner and idler pulleys as a preventive measure at 150k. I suspect they could have easily gone another 30k.

tia

That should have read cam magnets.