While true, classic cars are "simple" in that all of their parts can be replaced and remade in people's home garages with commercially available tools like lathes. If a chip breaks down, I doubt even in 100 years someone can make a replacement at home. In theory there will be a manufacturer or market with replacements, but it won't be easy.
It is substantially easier to replace the entire computer system of most gasoline engines if something critical like the ECU is no longer commanding the engine to deliver fuel or spark. In the US this constitutes a "defeat device" and is prohibited by federal law
It is possible to retrofit many old engines that didn't have an ECU with a modern fuel injection system.
My son drives a 1996 Buck Park Avenue which dates from the beginning of the ODB II era. We got it for about $4k but it has been through a few difficult repairs that took my son or auto techs a while to figure out. For instance the immobilizer system failed with the result that we couldn't start the car, it took a tech a lot of investigation to realize this, but once he did it wasn't hard to disable.
I suppose that hasn't been explored in the legal system currently. Most electric cars would be considered a zero emission vehicle. If you bolted a generator to an electric car that'd change its emissions. One could argue this defeats the original emissions target, but that sounds like a stretch.
Overall if the car has some sort of devices that limits, mitigates, or eliminates emissions then any modification to it can be considered a defeat device
I read it as agreeing with you by adding an interesting anecdote. Ie “yes, the old systems are easier to keep on the road. It would be possible to keep newer systems on the road with custom built parts (aftermarket ECU) but unfortunately that is illegal “
Carburetors are one of the most complex parts of a classic car and thus a bad example. If there are major carburetors problems it is probably simpler to replace it with fuel injection. (but only if a community of people work together - all the different maps and such in the ECU need to be created before you can make a useful fuel injection - this is long tedious work)
The ECU has fairly standardized interfaces, mostly CAN or just simple switching circuits on or off. You can just get a replacement ECU. These replacement ECUs generally don't do things like using the O2 sensor to adjust the fueling, so they can burn dirtier than the original ECU.
CAN is just the physical and framing layer. The data that goes over it is a whole different matter, and it's proprietary to every vendor, incompatible and generally undocumented.
For a lot of cars you can't even swap the exact same ECU between vehicles (due to bullshit like the VIN being written into it for no reason, and often no official way to change that other than "buy a new module" - so you have to hack around with reverse engineering & EEPROM programmers), let alone mix and match completely different parts.
There is good reason for this: theft protection. A long known crime model is the "chop shop" where they tow away a car, then cut it up for parts. Because the VIN is in the ECU a chop shop has less incentive to exist since there is less money in it.
It does of course make legitimate repairs harder, and probably there should be a process to write a new VIN in - but it should only be available to someone who can verify the ECU wasn't stolen (which isn't free).
EEPROM programmers and various other ways of rewriting this VIN (turnkey tools using undocumented diagnostic commands giving you unauthenticated read/write access to memory) means it's just one insignificant expense for the chop shop (as it's amortized over all their cars) vs a multi-thousand-dollar investment in money for a legitimate vehicle owner or part-time mechanic.
That's true, but it's usually pretty simple to reverse engineer, and that's been done for a lot of cars. CAN message are generally sent out at fixed time intervals, and correspond to some physical or control value, with a simple linear mapping between some physical unit and the value in the message. You collect some CAN data, change something like pressing the accelerator, see what changes, record results.
Just search for "aftermarket ECU", you'll find lots of them; generally for high-performance cars that gearheads want to soup up further, but the same basic principle applies to most ECUs.
Neither case is easy. Making something "simple" like a new control arm or connecting rod is way beyond a typical garage shop. The electronics are not a home shop item either but replacing parts with work-alike modules is already something people do with aftermarket ECUs etc. As long as there is enough demand people will find a way to make the parts (to supply aftermarket), for example I expect the first gen NSX to be repairable for decades.
I very much doubt cars with a lot of electronics and reliant of software and increasingly network connected are going to last that long anyway. The manufacturer stops updating software after 10 years if you are lucky and then its EOL and increasingly unsafe and insecure.
While true, classic cars are "simple" in that all of their parts can be replaced and remade in people's home garages with commercially available tools like lathes.
I've an '81 VW van in my driveway that begs to differ. It's got a bad idle stabilizer. The vehicle won't start unless that electronic idle stabilizer is bypassed. It runs fine in the bypass state, and good thing, because NOS parts ran out a few years ago. There might be efforts to create a clone (haven't checked thesamba.com in a while). I'm sure a clone is doable by someone that paid more attention in electronics class than I did, but no one is going to pop one out on their garage lathe.
And that's just the electronics. It has mechanical fuel injection (fuck you, Bosch), but good luck making injectors in your home workshop. I'll not start on suspension parts whose manufacturing require a far larger hydraulic press than anyone is likely to have in their garage.
It will require different skills though. One of them may well be reverse engineering, it's not as if the owners manual for a modern car includes schematics and source code.
