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Comment by lsc | Hacker News Reader

I still don't understand why people seem to think that modern cars are so difficult to work on compared to old junk. The onboard diagnostics is standardized and pretty good on most cars; that makes obvious many of your computer problems, timing problems and fuel/air problems.

I mean, most of my experience is working on fuel-injected stuff... but have you ever tried to rebuild a carb? it's damn difficult to get right, and there's no computer telling you when it's correct; you have to essentially guess.

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Having done extensive work on both old ('64 Ford Falcon, '68 Ford LTD) and new ('99 Eclipse, '00 S4) old cars are WAY easier to work on.

The first issue is simplicity and access. Old cars have big engine bays with everything spread out, easy to see, easy to get at. There are very few wires and it's pretty obvious (to a gearhead) what each component, wire, hose, etc... does. New cars have way more "stuff" packed into way less space. You can't see most things, and can't get at most things. There's a million wires, mostly run through harnesses, and plugged into various computers, etc...

Rebuilding a carb, while not easy, is easier than trying to diagnose if your poorly running engine is because of: bad MAF, bad O2 sensor(s) (some cars have 4-6 of these), bad O2 sensor wires (good luck tracking those through the various wire looms, etc...), bad computer(s), bad injector(s), bad FP, etc... Troubleshooting a throttle cable is easy compared to issues with a drive-by-wire system.

New cars are safer, perform better, handle better, etc... but working on them is a pain.

I have a counter point for ya:

Coming from an (amateur) electronics background, I can say the mechanical aspects seem just as opaque and confusing.

For example: Most electric systems can be tested with a multimeter and needlenose pliers. Repairs don't get more complex than soldering.

There's a garage full of specialized tools needed for the mechanical side of things. Checking fuel pressure, removing tires, etc.

Yes but even with modern cars you still need all the mechanical things, and things get way beyond a multimeter and a soldering iron on modern cars pretty quickly. There are many black-box computers, many complex sensors, thousands of wires that are next-to-impossible to trace/track through wire looms, the firewall, etc... I'm handy with a multimeter and a soldering iron, but still:)

You just need a diagram...I replaced all the wiring on a 1993 Mazda 626 from the front bumper to the dash. 4 big looms. If you have the "real" shop manual tracing problems is easy...not the Haynes or Chiltons (I have the original shop manuals for 2 of my 4 cars, including the electrical supplements, all wire color codings and methods to test every sensor are in the books.

I will not argue that fixing the main relay on my father's 1962 Thunderbird was way easier (I won't even get into the difference between dropping the fuel tank vs. a newer car) I believe for the most part newer cars are not much harder to work on. I really like what Volkswagen did with their VAG-Com stuff, really makes troubleshooting easy...like stupid easy, plus it interfaces with the laptop for datalogging.

I guess what I mean is most of those are closed systems which you need to replace entirely when they malfunction.

That's the best part of mechanical components for me: When it fails, often they just need to be cleaned.

I suspect that dirtying mechanical components have a higher TCO and/or failure frequency than total-failure electrical components.

I've recently had occasion to work on

1986 and 1990 Honda Civics: a PITA: just no space to turn a wrench in the engine compartment. Replacing a radiator took an absurd amount of time (and oh my aching back!)

1998 Toyota Sienna: replacing the radiator (w/engine cold) took 30 minutes the first time, 15 the second and third. My 13yo son displayed some interest so we did it an extra time :-). Changing the rear-cyl-bank O2 sensor (wedged against the firewall and crossmember) was a PITA.

1995 Camry w/same V6 engine as above Sienna: changing the same rear-bank O2 sensor was a breeze (bigger engine compartment).

Access is the key.

BTW I own two 1973 Toyota trucks, bought because they're simple to work on and exempt from CA smog testing (points ignition might survive the anticipated solar EMP!). And I agree that working with carbs is a black art with minimal feedback available, and EFI (real-time feedback!) is a major advance. Maybe EFI engines will "find their way" into these trucks :-)

my experience has been that the ease with which mechanical work can be done is directly proportional to the quality of your manual.

During the first .com, I owned a '92 bmw 325is. Fun car, but don't take it to a mechanic. I mean, parts weren't /that/ much more expensive, but mechanic time and parts markup was, I assume for the "well, if you can afford a bmw, you can help pay for my kid's braces" effect.

First I got the Chilton's brand "book of lies" and yeah, figuring out how to do even simple mechanical things was pretty difficult. I ended up wiring a bunch of stuff in with 24awg wire.

Later I bought the 'bently publishing' manual for the thing, and god damn. everything was really simple, and it all fit perfectly.

I know some people have gone from EFI to carbs on some motorcycles (KTM's early EFI offerings being the few I'm familiar with). I'd imagine it would be possible to go the other way, although I'm unsure of the difficulty of it.

"I mean, most of my experience is working on fuel-injected stuff... but have you ever tried to rebuild a carb? it's damn difficult to get right, and there's no computer telling you when it's correct; you have to essentially guess."

I tell mechanics around me this all the time (North Idaho)...I personally can rebuild and troubleshoot fuel injection with no issues, I have no idea how to tune a carb. Why? Simply because I haven't had to do that yet. People seem to be scared of anything with a computer, its always the ECU they replace first for some reason...usually the problem is a sensor or vacuum leak (from my experience with things).

Older cars are easier to work on because you typically have more room and fewer custom tools, plus you need very little electronics knowledge. I was an electronics tech before I started working on my own cars so I guess that helps.

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