5 ms·

That sounds like a terrible statement. Similar to a bridge engineer who wouldn't drive over a bridge he helped design. Shows a serious lack of trust in their c

by dpcx 13y ago

That sounds like a terrible statement. Similar to a bridge engineer who wouldn't drive over a bridge he helped design. Shows a serious lack of trust in their capabilities, and that of their team.

tjgq 13y ago
Or he could be referring to planned obsolescence.
mikeash 13y ago
I disagree. A failing bridge is a major safety problem, while a failing car engine is merely a financial problem. A bridge should last "forever", which is to say that it will be clear when it needs to be replaced before it actually fails. Car engines are routinely used until they break, then repaired and used until they break again, and this continues until it's no longer financially viable.
to3m 13y ago
It's not really very controversial. If you need your car, and you can't afford to buy a new engine if it breaks, as far as I can tell you'd be certainly well advised not run a modern diesel car without a warranty. I don't know anybody who's owned one who hasn't had various funny problems with it, requiring regular trips to the garage followed by shrugging shoulders all round and a succession of replacement of random electronic parts. To meet the increasingly stringent emissions controls, and people's desire for a car that is reasonably cheap and accelerates at a decent rate, the cars seem to have become rather complicated, and reliability has been affected. Common points of failure seem to be: - dual mass flywheel (presumably the regular swift ramping-up of torque doesn't help) - turbo charger (obviously spins very quickly and unlike a petrol engine it comes on from about 1500rpm so it's used a lot) - diesel injectors (high precision components operating under pressure) - diesel particulate filter (can clog and require expensive replacement if car is not regularly driven hard) - random engine/ECU "thing" that nobody can figure out (who knows what the root cause of this might be) You might have better luck with a pre-common rail diesel car, but the fuel economy is unlikely to be very good and the performance - at least by modern standards - looks to be terrible.
- grumps 13y ago
  The more electronic "stuffs" the greater the chance of an issue with it. What engines are you referring to in particular? Any brand in mind? Some manufacturers have been making diesels for a long time despite the emergence of common rail I'd suspect they would have most of this resolved now unless it's planned obsolescence
  - to3m 13y ago
    VW, Mercedes Benz and BMW are the brands I have these anecdotes for specifically. But reading on forums, it seems people have a lot of problems with modern diesel cars them generally. This is not exactly scientific, but the issue crops up at times in UK motoring and not-so-motoring press. Sample links: http://www.guardian.co.uk/money/2012/mar/02/turbo-charged-cost-of-diesel-cars http://www.guardian.co.uk/money/2012/mar/02/turbo-charged-co... http://www.thisismoney.co.uk/money/cars/article-2332107/Petrol-vs-diesel-cars-Drivers-warned-diesel-filter-trap.html http://www.thisismoney.co.uk/money/cars/article-2332107/Petr... http://www.telegraph.co.uk/motoring/news/9407960/The-hidden-cost-of-diesel-cars.html http://www.telegraph.co.uk/motoring/news/9407960/The-hidden-... http://www.which.co.uk/news/2012/07/petrol-cars-cheaper-to-run-than-diesel-291241/ http://www.which.co.uk/news/2012/07/petrol-cars-cheaper-to-r...
    - grumps 13y ago
      Thx
- fnordfnordfnord 13y ago
  >- turbo charger (obviously spins very quickly and unlike a petrol engine it comes on from about 1500rpm so it's used a lot) What's with the turbocharger FUD in here today? BTW 1500 RPM is 1/2 or 2/3 the way to the redline on many diesels, so it's not really used more than it would be on a gasoline engine. >- diesel injectors (high precision components operating under pressure) Really simple devices in principle, can get expensive for some vehicles when the engineers have gone around the bend with new features (Mercedes Sprinter, I'm looking at you). >- diesel particulate filter (can clog and require expensive replacement if car is not regularly driven hard) No experience with them. >- random engine/ECU "thing" that nobody can figure out (who knows what the root cause of this might be) Nonsense. This is a mechanic/technician training issue. Diesel ECU's are no more complicated than for a gasoline engine. I'm really surprised to see anyone on HN play the "Dang them fancy computers is too complicated fer me." card.

by dpcx 13y ago

That sounds like a terrible statement. Similar to a bridge engineer who wouldn't drive over a bridge he helped design. Shows a serious lack of trust in their capabilities, and that of their team.

tjgq 13y ago

Or he could be referring to planned obsolescence.

mikeash 13y ago

I disagree. A failing bridge is a major safety problem, while a failing car engine is merely a financial problem. A bridge should last "forever", which is to say that it will be clear when it needs to be replaced before it actually fails. Car engines are routinely used until they break, then repaired and used until they break again, and this continues until it's no longer financially viable.

to3m 13y ago

It's not really very controversial. If you need your car, and you can't afford to buy a new engine if it breaks, as far as I can tell you'd be certainly well advised not run a modern diesel car without a warranty. I don't know anybody who's owned one who hasn't had various funny problems with it, requiring regular trips to the garage followed by shrugging shoulders all round and a succession of replacement of random electronic parts. To meet the increasingly stringent emissions controls, and people's desire for a car that is reasonably cheap and accelerates at a decent rate, the cars seem to have become rather complicated, and reliability has been affected. Common points of failure seem to be: - dual mass flywheel (presumably the regular swift ramping-up of torque doesn't help) - turbo charger (obviously spins very quickly and unlike a petrol engine it comes on from about 1500rpm so it's used a lot) - diesel injectors (high precision components operating under pressure) - diesel particulate filter (can clog and require expensive replacement if car is not regularly driven hard) - random engine/ECU "thing" that nobody can figure out (who knows what the root cause of this might be) You might have better luck with a pre-common rail diesel car, but the fuel economy is unlikely to be very good and the performance - at least by modern standards - looks to be terrible.

grumps 13y ago
The more electronic "stuffs" the greater the chance of an issue with it. What engines are you referring to in particular? Any brand in mind? Some manufacturers have been making diesels for a long time despite the emergence of common rail I'd suspect they would have most of this resolved now unless it's planned obsolescence
- to3m 13y ago
  VW, Mercedes Benz and BMW are the brands I have these anecdotes for specifically. But reading on forums, it seems people have a lot of problems with modern diesel cars them generally. This is not exactly scientific, but the issue crops up at times in UK motoring and not-so-motoring press. Sample links: http://www.guardian.co.uk/money/2012/mar/02/turbo-charged-cost-of-diesel-cars http://www.guardian.co.uk/money/2012/mar/02/turbo-charged-co... http://www.thisismoney.co.uk/money/cars/article-2332107/Petrol-vs-diesel-cars-Drivers-warned-diesel-filter-trap.html http://www.thisismoney.co.uk/money/cars/article-2332107/Petr... http://www.telegraph.co.uk/motoring/news/9407960/The-hidden-cost-of-diesel-cars.html http://www.telegraph.co.uk/motoring/news/9407960/The-hidden-... http://www.which.co.uk/news/2012/07/petrol-cars-cheaper-to-run-than-diesel-291241/ http://www.which.co.uk/news/2012/07/petrol-cars-cheaper-to-r...
  - grumps 13y ago
    Thx
fnordfnordfnord 13y ago
>- turbo charger (obviously spins very quickly and unlike a petrol engine it comes on from about 1500rpm so it's used a lot) What's with the turbocharger FUD in here today? BTW 1500 RPM is 1/2 or 2/3 the way to the redline on many diesels, so it's not really used more than it would be on a gasoline engine. >- diesel injectors (high precision components operating under pressure) Really simple devices in principle, can get expensive for some vehicles when the engineers have gone around the bend with new features (Mercedes Sprinter, I'm looking at you). >- diesel particulate filter (can clog and require expensive replacement if car is not regularly driven hard) No experience with them. >- random engine/ECU "thing" that nobody can figure out (who knows what the root cause of this might be) Nonsense. This is a mechanic/technician training issue. Diesel ECU's are no more complicated than for a gasoline engine. I'm really surprised to see anyone on HN play the "Dang them fancy computers is too complicated fer me." card.