I was watching some video on people restoring black plastic trim on their cars (not rx7s) with a heat gun. The idea was they hit it with the heat gun directly to allow the moisture back into the plastic and bringing back the natural black shine without using chemicals. This seems easy and cool, but I don't think it would be good to do this on 30 year old plastic. I assume painting them is the best method to restore them? I'd love to hear some suggestions on paint and or methods done to restore these.

Secondly, my S4's body trim isn't shiny black and I like that it's not, I like the matte finish so I would like to keep that matte finish in a nice dark color.

Thanks

 

Ensure it's clean and then hit it with Dupli-Color Bumper and Trim paint.

 

Oh! I had no idea they sold spray specifically for that. Awesome, That's what I'll do. Thanks!

 

Here's how I did it.

Step 1:
Bucket of warm, soapy dish water. Dish soap is a good degreaser and surfactant. Gets a lot of the dirt off.
Scrubby sponge
Heavy application of elbow grease. You should have some on-hand for the rest of your vehicle.
Get them clean

Step 2:
Tub large enough to submerge pieces
Armorall trim protectant (comes in big jugs), or Mothers Back-to-Black trim restore (I haven't noticed a functional difference in the two products).
Rub in with rag, then submerge part in protectant for a few hours/days depending on how bad it was. Mine were fairly brittle, so I left them for about 2-3 days.
Wipe clean and inspect results

Here are pictures of the results. Parts are much more pliable, less brittle. I have since used the stuff on other plastic and rubber parts and it seems to do a pretty good job.





Best of luck

 

I just ordered some dupli-color bumper and trim paint, but yes, I'll be sure to give them a proper was before hand. I do own some Mothers "Back to Black" but honestly, I'm either not using it right or it doesn't work that well - I've tried it on side panel trim. Maybe the side trim is too smooth to absorb the product, but I wasn't too happy with it. I think a good clean and spray paint will give me the results I need considering the paint is made for that. I have some Simple Green that seems to do well on a lot of things. Would you say it's better to use soap and water or Simple Green? I'm just starting to learn about Simple Green so I don't know all of its Do's and Don'ts yet.

 

Are the side trim pieces clear-coated?

I'd say the porosity of the parts makes a big deal. I have tried it on the side trim yet, just mainly the plastic and rubber engine bay parts. I have been using a scotch brite sponge to scrub the surfaces. It might be opening up the pores in the process before I marinate them. I did notice it didn't work well on parts I just wiped off.

I can't speak for simple green. Some people swear by it. I've only used hot soapy water and haven't needed to try anything else

 

I wonder if they are clear coated. That would make obvious sense. I also tried Back to Black on my side mirrors (Black S4 mirrors, not painted) and it brought a little bit of shine to them but doesn't feel like it penetrated at all. Just felt like temporary surface shine. I'll for sure give it another try as I don't remember if I let it properly sit saturated with enough time to soak in.

 

Might take a couple applications as well, since the first is working on plastic that has dried out for 30 years. That top layer of plastic might loosen up and scrub off

if you don't want to use a whole jug, you can soak some shop rags, wrap the part, and put it somewhere away from the sun where it won't dry out. I didn't just wipe a layer on. It it were a newer part, that might work. I soaked mine for a few days. Putting time in to make up for the years of neglect

 

Thanks for the tips! I just put my parts in a bucket with soapy water. Gonna let that sit for a day or two then clean them with simple green to see what that looks like. My paint wont get here will Wednesday anyway so I got some time to get them nice and clean before paint. I like your suggestion on the saturated rag. I don't care if I use up most of a lot of the product so it's worth a shot!