Why your car is less reliable than it used to be

dsi1 > wrote:
>On 2/14/2014 6:56 AM, bob wrote:
>> http://edn.com/electronics-blogs/eng...it-used-to-be-
>
>The electronic controls are needed to meet car exhaust emission
>standards. We get to have cleaner air. It's a trade-off. I'm betting
>that cars will be more reliable and cheaper to run/maintain when we
>switch over to electric vehicles.

SOME of the electronic controls are needed to meet emission standards. The
development of fuel-injection systems with closed loop mixture control
was an enormous advance both in emissions and in efficiency. Not to
mention that it actually improved engine reliability... no more hard
starting in the cold. How long has it been since you heard of anyone
burning a valve from running too lean?

But honestly... do you really need the brake lights to be controlled off
a digital bus? Do you need the heads-up display with the GPS and the ipad
integration system? Do you need the heated seats and the feedback controls
for the AC that open and close the ducts to the rear seat area?

Cars _are_ less reliable than they used to be, because they are vastly more
complex than they used to be, because they have a lot of stupid junk on them.
But, in the end, they have all the stupid junk because the customers demand
it.

Electric vehicles have the promise of being more reliable because in some
ways they are more simple. There are only a few things to go wrong, so you
put all your engineering into making those few things more stable. However,
the cost-containment crew at GM is capable of making them just as flaky as
a Chevy Nova if they are permitted to do so.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

On 2/17/2014 11:41 AM, Scott Dorsey wrote:
> dsi1 > wrote:
>> On 2/14/2014 6:56 AM, bob wrote:
>>> http://edn.com/electronics-blogs/eng...it-used-to-be-
>>
>> The electronic controls are needed to meet car exhaust emission
>> standards. We get to have cleaner air. It's a trade-off. I'm betting
>> that cars will be more reliable and cheaper to run/maintain when we
>> switch over to electric vehicles.
>
> SOME of the electronic controls are needed to meet emission standards. The
> development of fuel-injection systems with closed loop mixture control
> was an enormous advance both in emissions and in efficiency. Not to
> mention that it actually improved engine reliability... no more hard
> starting in the cold. How long has it been since you heard of anyone
> burning a valve from running too lean?
>
> But honestly... do you really need the brake lights to be controlled off
> a digital bus? Do you need the heads-up display with the GPS and the ipad
> integration system? Do you need the heated seats and the feedback controls
> for the AC that open and close the ducts to the rear seat area?
>
> Cars _are_ less reliable than they used to be, because they are vastly more
> complex than they used to be, because they have a lot of stupid junk on them.
> But, in the end, they have all the stupid junk because the customers demand
> it.
>
> Electric vehicles have the promise of being more reliable because in some
> ways they are more simple. There are only a few things to go wrong, so you
> put all your engineering into making those few things more stable. However,
> the cost-containment crew at GM is capable of making them just as flaky as
> a Chevy Nova if they are permitted to do so.
> --scott
>

I was with you right up till you got to my very much _not_
flaky 65 Nova. Light and dependable but in no way flaky.

--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971

On 2/17/2014 7:41 AM, Scott Dorsey wrote:
> dsi1 > wrote:
>> On 2/14/2014 6:56 AM, bob wrote:
>>> http://edn.com/electronics-blogs/eng...it-used-to-be-
>>
>> The electronic controls are needed to meet car exhaust emission
>> standards. We get to have cleaner air. It's a trade-off. I'm betting
>> that cars will be more reliable and cheaper to run/maintain when we
>> switch over to electric vehicles.
>
> SOME of the electronic controls are needed to meet emission standards. The
> development of fuel-injection systems with closed loop mixture control
> was an enormous advance both in emissions and in efficiency. Not to
> mention that it actually improved engine reliability... no more hard
> starting in the cold. How long has it been since you heard of anyone
> burning a valve from running too lean?
>
> But honestly... do you really need the brake lights to be controlled off
> a digital bus? Do you need the heads-up display with the GPS and the ipad
> integration system? Do you need the heated seats and the feedback controls
> for the AC that open and close the ducts to the rear seat area?
>
> Cars _are_ less reliable than they used to be, because they are vastly more
> complex than they used to be, because they have a lot of stupid junk on them.
> But, in the end, they have all the stupid junk because the customers demand
> it.
>
> Electric vehicles have the promise of being more reliable because in some
> ways they are more simple. There are only a few things to go wrong, so you
> put all your engineering into making those few things more stable. However,
> the cost-containment crew at GM is capable of making them just as flaky as
> a Chevy Nova if they are permitted to do so.
> --scott
>

An electric car will be vastly more simple than the cars of today. The
drive train and controls would most likely be modular, standardized,
bolt-on units. The most complex part would be the power control box. My
guess is that the user will be able to configure their car by
programming the control unit to whatever performance level they want.
This is an exiting prospect. OTOH, self-driving cars could make personal
transportation as much fun as riding a bus.

On 2014-02-17, Scott Dorsey > wrote:
> dsi1 > wrote:
>>On 2/14/2014 6:56 AM, bob wrote:
>>> http://edn.com/electronics-blogs/eng...it-used-to-be-
>>
>>The electronic controls are needed to meet car exhaust emission
>>standards. We get to have cleaner air. It's a trade-off. I'm betting
>>that cars will be more reliable and cheaper to run/maintain when we
>>switch over to electric vehicles.
>
> SOME of the electronic controls are needed to meet emission standards. The
> development of fuel-injection systems with closed loop mixture control
> was an enormous advance both in emissions and in efficiency. Not to
> mention that it actually improved engine reliability... no more hard
> starting in the cold. How long has it been since you heard of anyone
> burning a valve from running too lean?
>
> But honestly... do you really need the brake lights to be controlled off
> a digital bus? Do you need the heads-up display with the GPS and the ipad
> integration system? Do you need the heated seats and the feedback controls
> for the AC that open and close the ducts to the rear seat area?

When one has to eek out every tiny bit of fuel economy having all
electric gizmos centrally controlled helps. Furthermore with things like
traction control, automatic braking and the like, a simple switch on the
brake pedal isn't enough. The computer has to turn the brake lights on
because it may be applying the brakes rather than the driver.

Also wires are cheaper than linkages and such. So the computer does all
that stuff too. The computer control also allows for heavier gauge wire
to be replaced with lighter gauge wire.

> Cars _are_ less reliable than they used to be, because they are vastly more
> complex than they used to be, because they have a lot of stupid junk on them.
> But, in the end, they have all the stupid junk because the customers demand
> it.

I have seen no math to support this. Component level reliability is
orders of magnitude better than many decades ago. The 1990s may be the
sweet spot between complexity and component reliability, but I haven't
seen any math or data to show it.

Brent > wrote:
>
>> Cars _are_ less reliable than they used to be, because they are vastly more
>> complex than they used to be, because they have a lot of stupid junk on them.
>> But, in the end, they have all the stupid junk because the customers demand
>> it.
>
>I have seen no math to support this. Component level reliability is
>orders of magnitude better than many decades ago. The 1990s may be the
>sweet spot between complexity and component reliability, but I haven't
>seen any math or data to show it.

Component level reliability has improved amazingly, but the number of
components has increased just as dramatically.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

On 2014-02-18, Scott Dorsey > wrote:
> Brent > wrote:
>>
>>> Cars _are_ less reliable than they used to be, because they are vastly more
>>> complex than they used to be, because they have a lot of stupid junk on them.
>>> But, in the end, they have all the stupid junk because the customers demand
>>> it.
>>
>>I have seen no math to support this. Component level reliability is
>>orders of magnitude better than many decades ago. The 1990s may be the
>>sweet spot between complexity and component reliability, but I haven't
>>seen any math or data to show it.
>
> Component level reliability has improved amazingly, but the number of
> components has increased just as dramatically.

Electronics should be operating at six sigma levels. The numbers haven't
increased that much even if you count each board level component.

Brent > wrote in
:

>
> Electronics should be operating at six sigma levels.



At least one Tier-1 supplier I used to work with was working to SEVEN
sigma. Or trying to, anyway. They had banners all over their plants saying
so.



--
Tegger