12 ms·

I work on my own cars now (as a hobby really) and one of the reasons the new cars are so expensive is they are much more complicated. A lot of this seems to be

I work on my own cars now (as a hobby really) and one of the reasons the new cars are so expensive is they are much more complicated. A lot of this seems to be over-engineering IMO. This is alluded to in the article, but not explicitly stated. The cars I work on are from the early 90s and everything is very simple to understand. e.g. Electronics are normally simple circuits that aren't much more complicated than what you would find in a door bell and finding faults is normally just tracing wires and using a multi-meter. I had issues with the brake lights / reverse lights not working, the issue turned out that the spade like connector in the fuse box was pushed through and was making partial contact. Price to fix this was £0. EDIT: Just remembered this isn't accurate. I had to buy a new reverse light. The entire reverse light assembly was ~£20. So the price to fix was about £20. The light assembly itself was like a big bicycle light. My newer car needs a OB-II scanner to diagnose anything with a phone app. While this is arguably quicker it can be misleading. Sometimes it will be telling you that something is malfunctioning but it is really the sensor itself. These sensors are £200-£300 a piece. Replacing 4 glow plug sensors cost me £800. I was paying essentially to make the "you must service your engine" light to go away. There was nothing wrong with engine itself.

LightBug1 1y ago
Same ... I'm still running an early 2000's Toyota and got myself a VW Beetle 1969 just for the fun of it ... love maintaining them as they're so simple and rewarding and parts are cheap! ... And I can in no way be called a mechanic. I've been lusting over the ioniq 5 for a couple of years but I'm just thinking, in 10 years time I'll be knee deep in your last paragraph ... I like long lasting cars
- BanterTrouble 1y ago
  Yep. There a bunch of minor issues with my vehicle that I was procrastinating on, but the brakes lights not working is very illegal and unsafe, so that had to be fixed before I drove it. Was really pleased once I realised what the issue and managed to fix it. All the newer cars feel like iPods with wheels and the driving experience is horrible. I am not interested in them.
Neikius 1y ago
Fully agree with what you are saying. I do have some beef with the prices of these electronic gadgets in the car. 300€ price for a new sensor or something similar? Sensor costs are usually a single digit or below. Somehow vendors found a way to inflate that price and this is destroying the repairability.
- BanterTrouble 1y ago
  With the prices of sensors, I was astonished and I thought the garage was having me on. I looked up the prices online and the garage weren't taking the mickey (it was withing 10-15% of what they quoted me).
- reliabilityguy 1y ago
  Car manufactures make probably more money on parts than selling new cars
  - throwaway173738 1y ago
    They do. But they make even more on interest from financing. And interest depends on the price you pay, so cheap cars cut into their profits.
a_c 1y ago
Any recommendation how to start learning repairing a car? I have absolutely zero experience. A friend of mine said just learn to change a tyre first and I have been procrastinating since.
- standeven 1y ago
  Commit to doing all the maintenance on your car yourself to start getting comfortable with it. Easy jobs to start: -replace cabin air filter -check for even tread wear -top up the wiper fluid -replace the windshield wipers -take off a wheel and look for tears in rubber bushings or grease leaking from seals. -replace anything broken like switches, trim pieces, etc. Assuming it’s a gas car: -replace engine air filter -inspect spark plugs -check fluid levels: brake fluid, engine oil, coolant -check 12V battery voltage with the engine off and also running -change the oil
  - smeej 1y ago
    Gosh, I didn't realize people weren't learning these things anymore, just as a matter of normal life. I'm an early(ish) Millennial woman from the suburbs, from a family with no meaningful mechanical knowledge or training of any kind, and I've done most of these things. I would have considered myself pretty ignorant about cars prior to reading your comment. Thanks for shifting my perspective to seeing myself as having at least a useful basic familiarity with things!
    - matwood 1y ago
      Great comment because I wondering the same thing. Do people not do any of those things on their own anymore? At a minimum, changing the oil was something I did with my dad as a kid. The hardest thing I've done was probably change a starter. ICE's are conceptually pretty simple. Anyone who has built a computer should be able to do basic car maintenance if they want to. The electronics is what makes newer cars more complicated, and I assume EVs even more so.
      - yks 1y ago
alerighi 1y ago
Yes, if they would make a basic car like in the past I would buy it. Everyone has to sell you too much, I want a simple car, I don't want either the stereo, I will add my own later (I can put it one that is better than the factory one for a cheaper price, but in a modern car replacing the stereo is almost impossible). There are a ton of useless sensors, the sensor that tells you if you have a flat tire (I think I can notice myself), the emergency call button (while everyone has a mobile phone these days), automatic regulating seats (pulling a lever is too much difficult), dual zone clima control (it's the same space in the same car, why I would want to set 2 different temperatures?), etc. And in all this useless things that they put in a car, they no longer provide you with a spare tire, just an useless repair kit...
- Hamuko 1y ago
  I presume you're gonna buy a Slate truck? https://www.slate.auto/en https://www.slate.auto/en
  - throwaway173738 1y ago
    Is it available in a hybrid or ICE?
  - idiotsecant 1y ago
    Yes!! If it turns out to be not vaporware, which lets be honest is probably a reasonably high probability.
  - ceejayoz 1y ago
    I don't want a truck, but if they do that approach for a minivan or a sedan, and they can get it to market, I'd 100% go for that. It sounds amazing.
- bumby 1y ago
  Some of those “useless” sensors like tire pressure or backup camera are required by law. Even if you get a bare bones hatchback (manual transmission, manual locks, manual windows etc.) they’ll be forced to include those.
lelanthran 1y ago
There's more to it than 'electronics'. Here's my more recent fixes: ----------------------------------- 1. The fuel pipe saga. Fuel pipe from pump (tank) to engine is a single, molded, hard-plastic and inflexible pipe. Connecting it to new quick release attachments on either end requires a heat gun. At the factory they can heat-shrink the connectors onto the pipes as there is no fuel in the car. When my quick-release snapped off[1] while I was replacing the fuel pump, dealer quoted my ZAR17,500 for a replacement pipe. To actually install it would require removing everything under the car because it is inflexible and molded to the shape of the car. Older cars had less efficient (i.e. thicker OD pipes with the same ID) fuel pipes, but they were flexible and easy to route. They used standard clamps which are available for cents right now. The advantage of the newer pipes is that: a) Cheaper to install (done by robots), and b) With the quick release joiner, easy for a robot to snap on the connections on either end. With the older, cheaper and repairable flexible pipes, the manufacturing process required a human. The more expensive pipes result in a cheaper-to-assemble car, even if the BOM is higher. ----------------------------------- 2. Heater blower motor refusing to come on. The AC units (including heater and blower motor) are controlled by low-current signals. This lets the unit have a rotary encoder when the human wants to adjust blower speed manually while still allowing the microcontroller to adjust blower speed when the user simply sets a target temperature. This requires an additional current-splitter to limit the current to the blower motor (controlling the speed) while maintaining the voltage. When the blower is spinning at a low speed current is dumped into a heat sink and the blower gets very little current. At high speed no current needs to be dumped and the blower can spin at full speed. My current limiter melted. This required a manufacturer-only replacement, as the digital signals controlling it are completely opaque to the technician (me) fixing the car.[2] Older cars without the rotary encoder had physical switches that switched the blower motor between one of 5 output speeds. Anything in the older system that broke can be replaced by standard switches and relays. Anything, even the smallest component, in the newer HVAC system that breaks means you have to hope like hell that the manufacturer is still making parts for the car. In this scenario, a 1995 mid-range car is going to outlive a 2025 mid-range sedan. ----------------------------------- 3. Engine and transmissions! This is the big one: a 2015 car that, after 20 years, has a worn out slushbox, might have to be thrown away! Why? Because if you are unable to replace the clutches and springs and other parts inside the slushbox due to lack of parts availability, you can't simply swap in a new one, or replace it with a manual - the car is going to throw up a dozen diagnostic codes and probably won't even start. That 1995 mid-range car? The engine and transmission are not coded to work with each other only. Swap in a Toyota v6 engine+transmission into a broke-ass Ford? Sure, why not? Same with the radio. In older cars the radio was a swappable unit with standard sizes. In new cars the infotainment system is rarely a regular shape, and in those cars where it is nothing but a screen, it's still hooked into the CAN bus to deliver warnings! You can upgrade your 1995 mid-range car to use the latest in infotainment technology (maps, voice commands, etc) by simply buying a head unit off Amazon. You cannot upgrade your top-off-the-range Range Rover, Mercedes Benz or Audi just 4 years after purchase! ----------------------------------- My point is this: the older cars can, with simple mechanical and electro-mechanical non-manufacturer parts, effectively run until humanity just doesn't have fuel anymore. The newer cars will, once the manufacturer stops producing parts for them, have to be scrapped. There is little incentive for the manufacturer to continue producing parts for a 10-year old car, and that gets even smaller as the car ages. In fact, I completely expect, as time goes on, that manufacturers would (if they haven't started already) code each component to the VIN or secret key so that parts from a breakers yard won't run in any other car even if it's the same model. Their preference is: When the radio breaks, it's time to buy a new car or live without a radio. -------------------- [1] Plastic that over time got brittle. [2] With a lot of work and lugging my ancient 'scope to the car, I could have worked out what signals were being sent (if digital; analogue would have been easier of course, requiring only a multimeter), designed a circuit around a MOSFET or similar and used a tiny microcontroller to read the signals and control the current.
Gareth321 1y ago
I think in time we see a similar trend with EVs. They are, by many metrics, vastly less complicated in terms of hardware. Software, of course, is another matter.
- cogman10 1y ago
  Software doesn't have to be complex. The most complex piece of software EVs absolutely need is the BMS and the charging protocol. Everything else is super basic. There's a reason some of the earliest vehicles were EVs.
  - dotancohen 1y ago
    You think that software isn't complex because you've never seen it. What should it do when the throttle pedal goes from 0 to 99 percent? That's likely an electrical issue, not a driver command to plow through the school zone. I could probably think of a dozen such scenarios, and the true number is probably in the hundreds. They all have to be proofed mathematically. With redundancy. Out of eye, out of mind.
    - cogman10 1y ago
      There is fundamentally no difference between a golf car and an electric car other than a higher top speed and more powerful motor. > What should it do when the throttle pedal goes from 0 to 99 percent? How fast? 0->99% in 1 second is likely the user gunning it. 0 to 99 percent in a millisecond is likely a fault. In either case, the simplest solution is a capacitor in-between the signal and throttle. Doesn't need to be particularly beefy to get the job done. The problem is you are thinking about this as a software problem when it's an electrical problem. There are a lot of electrical components that have instantaneous response times, well known curves, and perform exactly the jobs you'd want faster than what you can do with software. You want to minimize the amount of software between the accelerator and the motor precisely because you want to make the car as responsive as possible. Putting software in the middle creates delays and needs for very complex real time software and more expensive components.
doubled112 1y ago
I was shocked that we started replacing glow plugs one at a time. I drove a 2002 diesel Jetta for a few years. $80 for all four glow plugs. It’s a no brainer to do them all. This was probably ~2015, it was old when it was written off. This year, the cheapest I could find one (yes, just one) for my 2013 was $135 online. Cheaper online than a mechanic friend of mine could get it through any of his sources. There is a compression sensor in there now adding cost, apparently.
- geerlingguy 1y ago
  Aside, I had never heard of a glow plug, after working on a few generations of cars... I figured it might be a US vs rest of the world thing with naming something like a "spark plug". But I looked it up and for the benefit of anyone else who's never worked on diesel, it's part of the diesel ignition cycle it seems. TIL!
  - doubled112 1y ago
    A glow plug is basically a heater. Diesel being injected into the engine isn't ignited by a spark, but spontaneously by compression. This can't happen if the temperature in the cylinder is too low. Having your fuel being ignited by the engine running, as opposed to something like a spark plug, has interesting side effects like dieseling and runaway.
potato3732842 1y ago
> A lot of this seems to be over-engineering IMO. This is alluded to in the article, but not explicitly stated. I think a large part of the problem is that a sort of very scientific "modify a single variable at a time" type of engineering culture permeated academia a couple decades ago and now we're reaping what we sow. The sort of practical "I snipped this corner so now they pack neatly four to a box from the supplier and I altered that curve so now there's clearance for more types of wrenches around the bolt head and I smoothed out the rib shape for die longevity and in doing all that I reduced the mass by 6.5%" type stuff that engineering culture used to look up to has been replaced with KPI chasing "You told me to reduce mass by 6% and I reduced mass by 7%, 2nd and 3rd order consequences be damned" engineering culture that used to be fairly confined to the rich half of a certain continent is now what is worshipped. And likewise you get spiraling complexity because the only thing holding it back is the bean counters (when doing so is a priority) whereas before there was kind of natural restraint keeping it back on both sides. So as they go around updating platforms and models and sub-assemblies as whatnot the compliance ratchets up, unless the mandate at the time is to reduce it.
stronglikedan 1y ago
> The cars I work on are from the early 90s and everything is very simple to understand. If you were to take an older, simple to understand car, and add all of the modern features through aftermarket addons, you would end up with a car that is no longer simple to understand. They were simple to understand, because the feature set was simple compared to a modern car. (And I miss them dearly - can't wait to retire to find the time to find that love again!)
segmondy 1y ago
I read an article yesterday about how a simple nail puncture besides affecting tire sensor light, throws off traction control, abs, and all sorts of computing. what would be a 15 minutes patch and go job turns into an hour job of resetting computers and sensors.
- harambae 1y ago
  I recently had to replace a traction control sensor on my BMW -- it was a pain (and would've been expensive if I had a pro do it), so I can relate. But it's worth noting that modern traction-control makes life wildly safer for the average driver up north. I was driving an icy Vermont ski road with winter tires, but (because I hadn't yet fixed the sensor) no traction control. There were 2 pretty terrifying moments and I'm an experienced driver. Your average American can't even drive manual, there's no way they're compensating for low-traction winter mountain roads properly in all cases. I'd rank it more critical than any of the backup camera, TPMS or FCW features, and maybe on par with ABS for those of us in cold areas. Now if I lived in LA, I'd just hold down the "DTC" button to disable traction control on bootup and forget about it.
secabeen 1y ago
I found a similar thing on a cheap water heater. California requires an additional sensor to ensure the heating chamber doesn't overheat. It's not common generally, and the error messages when it triggers are not that helpful. After a few years of intermittent water heater failures, I finally realized that there was this sensor that was causing all the problems. I bypassed the sensor with a 1K resistor, confirming the issue, then had a new sensor sent out under warranty. Quick swap and it's been back to normal. I never found any documentation or repair advice that even considered that the sensor might be bad, and since it was California-only, most repair guides or technical documentation didn't mention it. It's really easy to have a sensor failure that indicates a major repair is needed, when the actual issue is the $1 sensor.

LightBug1 1y ago

Same ... I'm still running an early 2000's Toyota and got myself a VW Beetle 1969 just for the fun of it ... love maintaining them as they're so simple and rewarding and parts are cheap! ... And I can in no way be called a mechanic. I've been lusting over the ioniq 5 for a couple of years but I'm just thinking, in 10 years time I'll be knee deep in your last paragraph ... I like long lasting cars

BanterTrouble 1y ago
Yep. There a bunch of minor issues with my vehicle that I was procrastinating on, but the brakes lights not working is very illegal and unsafe, so that had to be fixed before I drove it. Was really pleased once I realised what the issue and managed to fix it. All the newer cars feel like iPods with wheels and the driving experience is horrible. I am not interested in them.

Neikius 1y ago

Fully agree with what you are saying. I do have some beef with the prices of these electronic gadgets in the car. 300€ price for a new sensor or something similar? Sensor costs are usually a single digit or below. Somehow vendors found a way to inflate that price and this is destroying the repairability.

BanterTrouble 1y ago
With the prices of sensors, I was astonished and I thought the garage was having me on. I looked up the prices online and the garage weren't taking the mickey (it was withing 10-15% of what they quoted me).
reliabilityguy 1y ago
Car manufactures make probably more money on parts than selling new cars
- throwaway173738 1y ago
  They do. But they make even more on interest from financing. And interest depends on the price you pay, so cheap cars cut into their profits.

a_c 1y ago

Any recommendation how to start learning repairing a car? I have absolutely zero experience. A friend of mine said just learn to change a tyre first and I have been procrastinating since.

standeven 1y ago
Commit to doing all the maintenance on your car yourself to start getting comfortable with it. Easy jobs to start: -replace cabin air filter -check for even tread wear -top up the wiper fluid -replace the windshield wipers -take off a wheel and look for tears in rubber bushings or grease leaking from seals. -replace anything broken like switches, trim pieces, etc. Assuming it’s a gas car: -replace engine air filter -inspect spark plugs -check fluid levels: brake fluid, engine oil, coolant -check 12V battery voltage with the engine off and also running -change the oil
- smeej 1y ago
  Gosh, I didn't realize people weren't learning these things anymore, just as a matter of normal life. I'm an early(ish) Millennial woman from the suburbs, from a family with no meaningful mechanical knowledge or training of any kind, and I've done most of these things. I would have considered myself pretty ignorant about cars prior to reading your comment. Thanks for shifting my perspective to seeing myself as having at least a useful basic familiarity with things!
  - matwood 1y ago
    Great comment because I wondering the same thing. Do people not do any of those things on their own anymore? At a minimum, changing the oil was something I did with my dad as a kid. The hardest thing I've done was probably change a starter. ICE's are conceptually pretty simple. Anyone who has built a computer should be able to do basic car maintenance if they want to. The electronics is what makes newer cars more complicated, and I assume EVs even more so.
    - yks 1y ago

alerighi 1y ago

Yes, if they would make a basic car like in the past I would buy it. Everyone has to sell you too much, I want a simple car, I don't want either the stereo, I will add my own later (I can put it one that is better than the factory one for a cheaper price, but in a modern car replacing the stereo is almost impossible). There are a ton of useless sensors, the sensor that tells you if you have a flat tire (I think I can notice myself), the emergency call button (while everyone has a mobile phone these days), automatic regulating seats (pulling a lever is too much difficult), dual zone clima control (it's the same space in the same car, why I would want to set 2 different temperatures?), etc. And in all this useless things that they put in a car, they no longer provide you with a spare tire, just an useless repair kit...

Hamuko 1y ago
I presume you're gonna buy a Slate truck? https://www.slate.auto/en https://www.slate.auto/en
- throwaway173738 1y ago
  Is it available in a hybrid or ICE?
- idiotsecant 1y ago
  Yes!! If it turns out to be not vaporware, which lets be honest is probably a reasonably high probability.
- ceejayoz 1y ago
  I don't want a truck, but if they do that approach for a minivan or a sedan, and they can get it to market, I'd 100% go for that. It sounds amazing.
bumby 1y ago
Some of those “useless” sensors like tire pressure or backup camera are required by law. Even if you get a bare bones hatchback (manual transmission, manual locks, manual windows etc.) they’ll be forced to include those.

lelanthran 1y ago

There's more to it than 'electronics'. Here's my more recent fixes: ----------------------------------- 1. The fuel pipe saga. Fuel pipe from pump (tank) to engine is a single, molded, hard-plastic and inflexible pipe. Connecting it to new quick release attachments on either end requires a heat gun. At the factory they can heat-shrink the connectors onto the pipes as there is no fuel in the car. When my quick-release snapped off[1] while I was replacing the fuel pump, dealer quoted my ZAR17,500 for a replacement pipe. To actually install it would require removing everything under the car because it is inflexible and molded to the shape of the car. Older cars had less efficient (i.e. thicker OD pipes with the same ID) fuel pipes, but they were flexible and easy to route. They used standard clamps which are available for cents right now. The advantage of the newer pipes is that: a) Cheaper to install (done by robots), and b) With the quick release joiner, easy for a robot to snap on the connections on either end. With the older, cheaper and repairable flexible pipes, the manufacturing process required a human. The more expensive pipes result in a cheaper-to-assemble car, even if the BOM is higher. ----------------------------------- 2. Heater blower motor refusing to come on. The AC units (including heater and blower motor) are controlled by low-current signals. This lets the unit have a rotary encoder when the human wants to adjust blower speed manually while still allowing the microcontroller to adjust blower speed when the user simply sets a target temperature. This requires an additional current-splitter to limit the current to the blower motor (controlling the speed) while maintaining the voltage. When the blower is spinning at a low speed current is dumped into a heat sink and the blower gets very little current. At high speed no current needs to be dumped and the blower can spin at full speed. My current limiter melted. This required a manufacturer-only replacement, as the digital signals controlling it are completely opaque to the technician (me) fixing the car.[2] Older cars without the rotary encoder had physical switches that switched the blower motor between one of 5 output speeds. Anything in the older system that broke can be replaced by standard switches and relays. Anything, even the smallest component, in the newer HVAC system that breaks means you have to hope like hell that the manufacturer is still making parts for the car. In this scenario, a 1995 mid-range car is going to outlive a 2025 mid-range sedan. ----------------------------------- 3. Engine and transmissions! This is the big one: a 2015 car that, after 20 years, has a worn out slushbox, might have to be thrown away! Why? Because if you are unable to replace the clutches and springs and other parts inside the slushbox due to lack of parts availability, you can't simply swap in a new one, or replace it with a manual - the car is going to throw up a dozen diagnostic codes and probably won't even start. That 1995 mid-range car? The engine and transmission are not coded to work with each other only. Swap in a Toyota v6 engine+transmission into a broke-ass Ford? Sure, why not? Same with the radio. In older cars the radio was a swappable unit with standard sizes. In new cars the infotainment system is rarely a regular shape, and in those cars where it is nothing but a screen, it's still hooked into the CAN bus to deliver warnings! You can upgrade your 1995 mid-range car to use the latest in infotainment technology (maps, voice commands, etc) by simply buying a head unit off Amazon. You cannot upgrade your top-off-the-range Range Rover, Mercedes Benz or Audi just 4 years after purchase! ----------------------------------- My point is this: the older cars can, with simple mechanical and electro-mechanical non-manufacturer parts, effectively run until humanity just doesn't have fuel anymore. The newer cars will, once the manufacturer stops producing parts for them, have to be scrapped. There is little incentive for the manufacturer to continue producing parts for a 10-year old car, and that gets even smaller as the car ages. In fact, I completely expect, as time goes on, that manufacturers would (if they haven't started already) code each component to the VIN or secret key so that parts from a breakers yard won't run in any other car even if it's the same model. Their preference is: When the radio breaks, it's time to buy a new car or live without a radio. -------------------- [1] Plastic that over time got brittle. [2] With a lot of work and lugging my ancient 'scope to the car, I could have worked out what signals were being sent (if digital; analogue would have been easier of course, requiring only a multimeter), designed a circuit around a MOSFET or similar and used a tiny microcontroller to read the signals and control the current.

Gareth321 1y ago

I think in time we see a similar trend with EVs. They are, by many metrics, vastly less complicated in terms of hardware. Software, of course, is another matter.

cogman10 1y ago
Software doesn't have to be complex. The most complex piece of software EVs absolutely need is the BMS and the charging protocol. Everything else is super basic. There's a reason some of the earliest vehicles were EVs.
- dotancohen 1y ago
  You think that software isn't complex because you've never seen it. What should it do when the throttle pedal goes from 0 to 99 percent? That's likely an electrical issue, not a driver command to plow through the school zone. I could probably think of a dozen such scenarios, and the true number is probably in the hundreds. They all have to be proofed mathematically. With redundancy. Out of eye, out of mind.
  - cogman10 1y ago
    There is fundamentally no difference between a golf car and an electric car other than a higher top speed and more powerful motor. > What should it do when the throttle pedal goes from 0 to 99 percent? How fast? 0->99% in 1 second is likely the user gunning it. 0 to 99 percent in a millisecond is likely a fault. In either case, the simplest solution is a capacitor in-between the signal and throttle. Doesn't need to be particularly beefy to get the job done. The problem is you are thinking about this as a software problem when it's an electrical problem. There are a lot of electrical components that have instantaneous response times, well known curves, and perform exactly the jobs you'd want faster than what you can do with software. You want to minimize the amount of software between the accelerator and the motor precisely because you want to make the car as responsive as possible. Putting software in the middle creates delays and needs for very complex real time software and more expensive components.

doubled112 1y ago

I was shocked that we started replacing glow plugs one at a time. I drove a 2002 diesel Jetta for a few years. $80 for all four glow plugs. It’s a no brainer to do them all. This was probably ~2015, it was old when it was written off. This year, the cheapest I could find one (yes, just one) for my 2013 was $135 online. Cheaper online than a mechanic friend of mine could get it through any of his sources. There is a compression sensor in there now adding cost, apparently.

geerlingguy 1y ago
Aside, I had never heard of a glow plug, after working on a few generations of cars... I figured it might be a US vs rest of the world thing with naming something like a "spark plug". But I looked it up and for the benefit of anyone else who's never worked on diesel, it's part of the diesel ignition cycle it seems. TIL!
- doubled112 1y ago
  A glow plug is basically a heater. Diesel being injected into the engine isn't ignited by a spark, but spontaneously by compression. This can't happen if the temperature in the cylinder is too low. Having your fuel being ignited by the engine running, as opposed to something like a spark plug, has interesting side effects like dieseling and runaway.

potato3732842 1y ago

> A lot of this seems to be over-engineering IMO. This is alluded to in the article, but not explicitly stated. I think a large part of the problem is that a sort of very scientific "modify a single variable at a time" type of engineering culture permeated academia a couple decades ago and now we're reaping what we sow. The sort of practical "I snipped this corner so now they pack neatly four to a box from the supplier and I altered that curve so now there's clearance for more types of wrenches around the bolt head and I smoothed out the rib shape for die longevity and in doing all that I reduced the mass by 6.5%" type stuff that engineering culture used to look up to has been replaced with KPI chasing "You told me to reduce mass by 6% and I reduced mass by 7%, 2nd and 3rd order consequences be damned" engineering culture that used to be fairly confined to the rich half of a certain continent is now what is worshipped. And likewise you get spiraling complexity because the only thing holding it back is the bean counters (when doing so is a priority) whereas before there was kind of natural restraint keeping it back on both sides. So as they go around updating platforms and models and sub-assemblies as whatnot the compliance ratchets up, unless the mandate at the time is to reduce it.

stronglikedan 1y ago

> The cars I work on are from the early 90s and everything is very simple to understand. If you were to take an older, simple to understand car, and add all of the modern features through aftermarket addons, you would end up with a car that is no longer simple to understand. They were simple to understand, because the feature set was simple compared to a modern car. (And I miss them dearly - can't wait to retire to find the time to find that love again!)

segmondy 1y ago

I read an article yesterday about how a simple nail puncture besides affecting tire sensor light, throws off traction control, abs, and all sorts of computing. what would be a 15 minutes patch and go job turns into an hour job of resetting computers and sensors.

harambae 1y ago
I recently had to replace a traction control sensor on my BMW -- it was a pain (and would've been expensive if I had a pro do it), so I can relate. But it's worth noting that modern traction-control makes life wildly safer for the average driver up north. I was driving an icy Vermont ski road with winter tires, but (because I hadn't yet fixed the sensor) no traction control. There were 2 pretty terrifying moments and I'm an experienced driver. Your average American can't even drive manual, there's no way they're compensating for low-traction winter mountain roads properly in all cases. I'd rank it more critical than any of the backup camera, TPMS or FCW features, and maybe on par with ABS for those of us in cold areas. Now if I lived in LA, I'd just hold down the "DTC" button to disable traction control on bootup and forget about it.

secabeen 1y ago

I found a similar thing on a cheap water heater. California requires an additional sensor to ensure the heating chamber doesn't overheat. It's not common generally, and the error messages when it triggers are not that helpful. After a few years of intermittent water heater failures, I finally realized that there was this sensor that was causing all the problems. I bypassed the sensor with a 1K resistor, confirming the issue, then had a new sensor sent out under warranty. Quick swap and it's been back to normal. I never found any documentation or repair advice that even considered that the sensor might be bad, and since it was California-only, most repair guides or technical documentation didn't mention it. It's really easy to have a sensor failure that indicates a major repair is needed, when the actual issue is the $1 sensor.