OK, guys, today I wanted to check out the spark plugs and discovered that those rubber "dildos" (I don't know the correct term so I'll just use this one ) that connect the coils with the spark plugs have different kOhm ratings?! Wtf?

Two of my coils are original BMW (BREMI) and have 1.8k Ohm dildo attached to it, and 4 of them are Bosch which have 1k Ohm dildos. I also noticed that those parts have different part numbers. I suppose this isn't right, ay?

I also noticed that those original BREMI coils are starting to develop some candy underneath - not much, just a few mm, but still visible. Should I swap them now before they fry my Motronic? Could this be the reason for a slightly lumpy idle and hesitation in lower rpm range?

Btw., I suspect my valve cover gasket is leaking - I found some oil in one of the spark plug holes and the rubber dildo had oil on it so I guess it's dripping from above?