Over the past few months I've noticed the fake black vents on my BRZ were turning white around the corners. I tried using soap and water, and detailer to clean them but they'd look fine for 5 minutes or so and turn back white after they dried. After looking at what DetailersDomain (DD) did restoring the plastic trim parts of a Porsche using BLACK WOW, I decided to get some for my BRZs fender trim. At $30 a bottle, it's kind of pricey but I may have found a cheaper alternative during the prep work for the black wow. See below.
DD and the back of the bottle recommends not getting any Black Wow on to the paint so I figured the best way to accomplish this is to remove the vents. The plan was to do the Driver side and remember everything from the process then take pictures when I do the passenger side.
The first thing I did was pull out the fake vent, that took less than a minute. I then spent the next half an hour pulling what was left of the 3M tape off of the fender trim still attached to the car. I was able to get 99% of it by just using my fingers. I didn't want to spend another 30 minutes removing the tape bits from the vent so I decided to spray some Adams All Purpose Cleaner on the tape in hopes it would make it easier to remove. It didn't, but I did notice that the vent side that got wet with the APC wasn't turning white. So I sprayed the whole vent side with the APC and wiped it with a paper towel and watched as it stayed black after about 5 minutes. (wishing I hadn't begun by pulling it out).
Moving back to the tape on the other side of the vent; I tried a number of other cleaners and finally remembered I had a spray can of Krylon Adhesive Remover that worked like magic to remove the glue (not sure how it will react to paint). I then moved on to the other vent with the hopes of just using all purpose cleaner to get rid of the fading.
Here's how it started out
And here's how it was after wiping it down with APC and a paper towel. I took the picture about 20 minutes after I applied the APC.
Pretty awesome huh?
I then read the instruction on the back of the bottle and noticed it said something along the lines of spraying the cleaned part with high pressure water. I did the next best thing, I used a spray bottle... and after some wiping I got this (same thing happened with the drivers side):

Some discoloration is back, but it isn't as bad as it was before. I decided to let it dry fully over night to see what happens. Maybe a second cleaning tomorrow will take the white out completely?
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I wasn't happy with the fading returning even if it was just a little, so I decided to go ahead and apply the Black Wow to the drivers side so I could compare the two. Right now the plan is to just apply it to the drivers side, then re-examine them both in a month.
The instructional video for the Black Wow says to first clean the part with a 50:50 mix of Rubbing Alcohol and water so I did that using a tooth brush. I took the pictures in my bathroom so they came out kind of dark. You can't really see it in the picture but the fading is visible in the vent.
I then applied the Black Wow. I think it looked really good, just a bit glossy.
Then, following the directions, I wiped it down with a microfiber then rinsed it off with water and dried it.

Rinsed with water:
I'll take a picture tomorrow comparing the drivers side and passenger side.
That's it for now.