I had some project ideas for my 2004 Mazda RX-8 that involved tapping power from its auto-dimming rear view mirror. After determining its power connector pinout, I realized I wasn’t excited to keep going. This marks the end of a chain of events that started with a puddle of coolant demanding my attention to find the leak. I think I’m done with car projects for a bit. I’m writing down my current thoughts which may or may not hold up in the future with more hindsight wisdom.

A big part of keeping an old car running is replacing or repairing old worn out parts. As a car of early 2000s vintage, my RX-8 has lots of plastic and rubber pieces that have become brittle and fragile with age such as the radiator I just replaced. Paradoxically, much older cars may be easier to keep running because more of their parts were made of metal. It’s not very satisfying to replace plastic and rubber pieces that were only designed to survive duration of the warranty.

I did learn quite a few things as I worked my way to the radiator, understanding more of what’s under the hood. I now recognize hoses not just between the engine and radiator, I also recognize hoses leading to the coolant reservoir and leading back towards the interior heater core. This is similar to the thrill I get from teardowns, but that thrill is diminished by many annoyances. The first is that age throws barriers in my way — like stubborn hoses — that are not illuminating and not fun to solve. The second is that, unlike most of my teardown projects, I have to put this thing back together afterwards!

21st century cars also tend to be very cramped under the hood, making everything hard to access compared to the relative wide open spaces under the hood of something from the 1960s. So many sensors, wires, and hoses are packed in there and every single one is a potential point of failure. Parts availability dry up as cars get older, but this problem is worse for low volume cars like a RX-8. Parts are expensive when they are available at all. This is a problem shared with most cars that date back to the 1960s, the difference is that it’s much easier to design and fabricate a substitute. For a 1960s car, it’s likely something mechanical that can be built in a home workshop. For a 2004 car, good luck fabricating a replacement sensor that can keep the engine control unit (ECU) happy. And there’s a risk of such a project going sour killing the ECU, which would turn a small problem into a huge one.

Some people work on their cars to make it uniquely their own and feel a connection to it. I can certainly understand that and I’ve played around with it myself. But projects like retrofitting Android Auto and a backup camera aren’t breaking any ground. (New cars just come with that stuff now.) Neither is a dashcam, so I don’t think it’s going to happen.