Quoted from MUGEN_4_LIFE:I just had to swap out all three of my coil stops last night. The right flipper was sticking and I knew right away it was probably the coil stop since my AIQ had this issue at around 6mos old. I assumed I'd just change them out as they went bad but when I pulled playfield into service pos there was gold dust under all three flipper assemblies and the coils stops were all spinning freely . I was hoping Stern fixed this but obviously they're still using poor quality parts all around. Im going to see if they'll send me some replacement coil stops since the games not even five months old yet. I will keep them on hand when another fails.
It's not even worth it to take free replacement garbage coil stops from Stern since they will also fail too quickly in most cases. Stern essentially is using the "starter ink/toner" model to save a few cents per machine. Give you just enough to make it work, leave you on the hook for the long-term part when your factory "starter" coil stop time is quickly up.
Just pay the $5 for the reliable pinball life ones and you won't be changing them for a long time.