Front fenders - should I replace the the foam?

[Jimal]

While swapping a new LF fender onto my 2015 GTI yesterday, I came upon two related issues that I wasn't expecting. First was the amount of mud built up inside the fender between the liner and the door. I'm assuming that was rotting leaves and organic material fell through the cowl drains and settled in there. I was able to clean that out with the fender off. The second issue, which I wasn't able to address because I needed to put the car back together was that the bottom of the foam insulator that fills in gap between the fender and the pillar was absolutely saturated with water. As I moved it out of the way to access the two bolts at the bottom of fender, the water just poured out. The replacement fender didn't have this foam, so I peeled it off the old fender, stuffed it into place, and put installed the new fender.

Has anyone else run into this? I'm thinking about ordering new foam for both sides, then taking the front fenders and bumper off and really going to town with a hose or pressure washer to clean out all that debris. There's no rust yet, but all that moisture is just asking for it to happen.

 

[ZERO815]

Same issue here. Ran into it last year on my ‘17. Replaced it with the facelift plastic/rubber version (don’t have the part number).
No need to take fender and bumper off. Take door out and inner fender. Enough room to remove, clean and reinstall.

Picture was taken before new piece was properly installed. Now the rubber seals perfectly.

 

[Jimal]

Same exact muck. I have the P/Ns for the original foam blocks (5G0821111/2) and what appears to be the replacements (5H0821111/2). Might take a stab at pulling the fender liners, rinsing everything thoroughly, and letting it sit apart like that to dry out. If it doesn't dry to my satisfaction, order the parts and stick them in.