Should I replace this coil?

[copperhead]

http://i412.photobucket.com/albums/pp201/copperhead035/IMG_20140519_025500_zpsovjreexs.jpg

 

Here's the plug that was attached to it (it's been replaced)

 

http://i412.photobucket.com/albums/pp201/copperhead035/IMG_20140519_025430_zpsezczsm6y.jpg

 

Not the best picture, I know. Around the nut part of it was what looked like rust.

 

Car in question is a 2013 VW Passat 2.5 that's just about to 50,000 miles. I assume it's the first plug change. The browned coil is the one on the far left side (drive side), dunno if that's cylinder #1 or #5. Everything else looked fine.

[Cordell]

So what caused that? Was there water or oil down in that hole. Spark plugs tend to corrode and rust on the top side of the hex either way so I'm not sure that proves water intrusion. Did the car run bad or misfire? I don't have any real world experience with VWs to even know what's typical of them, but if it were just my car and it ran fine, I'd just use it. However without knowing the cause, I doubt I'd want to leave that on a customers car, but I'd want to know why so it didn't happen again.

[93 RX-7]

^^^ agreed. Need more info. Did the staining wipe off? Or was it permanent? Looked kind of powdery in the pic.

[copperhead]

I didn't think to wipe it off, I was pretty worn out by the time I got to that. I'd totally forgotten I'd made this post about it.

 

Car was running fine. All of the holes had some sort of red grease in them, didn't notice any water.

[grease monkey]

vw - Replace all coils and plugs. at least once per year.