I checked my crank pos sens as a last resort for a misfire/under idle whatever it is, thats happening upon restart of a warm engine. this is what i found:

-a little bit of sludge/grease on one of the contacts
-metal shavings stuck to the sensor
-one contact a little recessed compared to the other that was flush

i know that metal shavings isn't good but what could cause this so it doesn't happen again.
and, is it possible that this could be the cause of my problem?

thanks