240z Tail Light Gaskets
Nobody wants to smell exhaust inside their car. Here's a cheap way to fix it.
Every car has quirks and a 240z is no exception. The aerodynamics at the rear creates a pressure zone. If the gaskets around your tail lights are cracked or have shrunken, that pressure zone can push exhaust fumes inside the cabin. Opening a window can make it worse because it creates a slight vacuum, helping draw more of the fumes in. At the least it'll be stinky but at the worst it can be dangerous because the exhaust contains (among other things) carbon monoxide, which can kill. The solution is to replace the gaskets but they can be pricey. Some people have used caulking as a cheap alternative but it can be pretty messy. Why not make your own gaskets? It's cheap and easy. Here's how it's done
Stock Replacement Gaskets
Here's what a stock gasket looks like. It's made from thin rubber, molded to fit around the plastic housing. They work pretty well unless the tail light housing is cracked or warped.
The worst part is they aren't cheap. In 2022 the cheapest pair I could find was $87 plus $10 shipping.
Neoprene Foam
My solution was to buy some adhesive-back neoprene foam. This roll is 1/4-inch thick, 12" wide and 24" long. Neoprene is flexible but fairly rugged and is typically used for wetsuits. It's also the perfect material for gasketsbecause it'll fill any gaps.
It's easy to cut with a pair of scissors or a razor blade. The adhesive backing holds it tight.
This roll was just $20 with free shipping. That's a 79% savings.
Making The Gasket
With some paper and tape I made a simple template in about 10 minutes.
On the back of the neoprene is a sheet of peel-off paper to protect the adhesive. Use a pen or Sharpie on that paper to trace the template.
The gaskets are mirror-image, so flip the template over to make the other one.
A metal straightedge helped make a smooth cut, but since the gasket won't been seen, scissors will work fine.
The Final Product
Here's how it looks affixed to the tail light housing.
I did this with mine and (so far) I haven't smelled any exhaust or gasoline fumes.
Side Tip 1: Pick up some plastic polish at your local parts store and use it to clean the tail light lenses inside & out.
Side Tip 2: Inside the housing, where the bulbs sit, is a very thin layer of reflective mylar. It helps make the tail lights a little brighter. The mylar on yours might be faded or peeling away. I gave mine a quick sanding, then used some "chrome" rattle-can paint to restore the mirror finish. Worked great.
Side Tip 3: While you have everything apart, why not replace the stock incandescent bulbs with new LED versions?