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| Science Forum Index » Electronics - Design Forum » OT: for JT, Toyota Runway Cars... |
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| Martin Riddle... |
 Posted: Thu Nov 05, 2009 7:45 pm |
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| Jim Thompson... |
| Posted: Thu Nov 05, 2009 7:54 pm |
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On Thu, 5 Nov 2009 19:45:34 -0500, "Martin Riddle"
<martin_rid at (no spam) verizon.net> wrote:
[quote]http://abcnews.go.com/Blotter/RunawayToyotas/
[/quote]
My #2 Daughter's Lexus has been checked out... push into neutral,
coast to a stop with power-assisted steering and brakes.
I haven't been able to confirm if Toyota's have an RPM limiter to
prevent over-revving and blowing an engine. I know I personally was
designing such electronics clear back in the mid '60's, for Ford, GM
_and_ Chrysler vehicles. Some of those big block V-8's could
otherwise be pushed out to 9-10 kRPM before rods and other debris
issued forth 
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Obama says, "I AM NOT a cry baby, Fox REALLY IS out to get me!" |
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| Joerg... |
| Posted: Thu Nov 05, 2009 7:59 pm |
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Jim Thompson wrote:
[quote]On Thu, 5 Nov 2009 19:45:34 -0500, "Martin Riddle"
martin_rid at (no spam) verizon.net> wrote:
http://abcnews.go.com/Blotter/RunawayToyotas/
My #2 Daughter's Lexus has been checked out... push into neutral,
coast to a stop with power-assisted steering and brakes.
I haven't been able to confirm if Toyota's have an RPM limiter to
prevent over-revving and blowing an engine. I know I personally was
designing such electronics clear back in the mid '60's, for Ford, GM
_and_ Chrysler vehicles. Some of those big block V-8's could
otherwise be pushed out to 9-10 kRPM before rods and other debris
issued forth :-(
[/quote]
Some Volkswagens had that even earlier. A simple governor on top of the
distributor which shorted the whole works if over-revved. Some people
routinely drove them that high and then you could hear the engine cut in
and out really fast, something like 3-5 Hertz.
--
Regards, Joerg
http://www.analogconsultants.com/
"gmail" domain blocked because of excessive spam.
Use another domain or send PM. |
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| Jim Thompson... |
| Posted: Thu Nov 05, 2009 8:02 pm |
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On Thu, 05 Nov 2009 16:59:12 -0800, Joerg <invalid at (no spam) invalid.invalid>
wrote:
[quote]Jim Thompson wrote:
On Thu, 5 Nov 2009 19:45:34 -0500, "Martin Riddle"
martin_rid at (no spam) verizon.net> wrote:
http://abcnews.go.com/Blotter/RunawayToyotas/
My #2 Daughter's Lexus has been checked out... push into neutral,
coast to a stop with power-assisted steering and brakes.
I haven't been able to confirm if Toyota's have an RPM limiter to
prevent over-revving and blowing an engine. I know I personally was
designing such electronics clear back in the mid '60's, for Ford, GM
_and_ Chrysler vehicles. Some of those big block V-8's could
otherwise be pushed out to 9-10 kRPM before rods and other debris
issued forth :-(
Some Volkswagens had that even earlier. A simple governor on top of the
distributor which shorted the whole works if over-revved. Some people
routinely drove them that high and then you could hear the engine cut in
and out really fast, something like 3-5 Hertz.
[/quote]
I've done that, too, on Ford products ;-)
Duane's "replacement" was just showing me his new Subaru toy with a
horizontally opposed 4-banger... 2.5L, blower, 270hp 
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Obama says, "I AM NOT a cry baby, Fox REALLY IS out to get me!" |
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| krw... |
| Posted: Thu Nov 05, 2009 8:06 pm |
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On Thu, 05 Nov 2009 16:59:12 -0800, Joerg <invalid at (no spam) invalid.invalid>
wrote:
[quote]Jim Thompson wrote:
On Thu, 5 Nov 2009 19:45:34 -0500, "Martin Riddle"
martin_rid at (no spam) verizon.net> wrote:
http://abcnews.go.com/Blotter/RunawayToyotas/
My #2 Daughter's Lexus has been checked out... push into neutral,
coast to a stop with power-assisted steering and brakes.
I haven't been able to confirm if Toyota's have an RPM limiter to
prevent over-revving and blowing an engine. I know I personally was
designing such electronics clear back in the mid '60's, for Ford, GM
_and_ Chrysler vehicles. Some of those big block V-8's could
otherwise be pushed out to 9-10 kRPM before rods and other debris
issued forth :-(
Some Volkswagens had that even earlier. A simple governor on top of the
distributor which shorted the whole works if over-revved. Some people
routinely drove them that high and then you could hear the engine cut in
and out really fast, something like 3-5 Hertz.
[/quote]
Kinda like 5 O'clock Charlie. |
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| ChrisQ... |
| Posted: Fri Nov 06, 2009 11:01 am |
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Joerg wrote:
[quote]
Some Volkswagens had that even earlier. A simple governor on top of the
distributor which shorted the whole works if over-revved. Some people
routinely drove them that high and then you could hear the engine cut in
and out really fast, something like 3-5 Hertz.
[/quote]
Same stable, my old 1985 Audi 90 Q was like that, using a spring loaded
rotor arm tip. Modern engines are all electronic though and the
limiting's done in software. Usually with no mechanical override .
Regards,
Chris |
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| langwadt at (no spam) fonz.dk... |
| Posted: Fri Nov 06, 2009 2:15 pm |
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On 7 Nov., 00:08, Jim Thompson <To-Email-Use-The-Envelope-I... at (no spam) My-Web-
Site.com> wrote:
[quote]On Sat, 07 Nov 2009 06:59:05 +0800, who where <no... at (no spam) home.net> wrote:
On Thu, 5 Nov 2009 19:45:34 -0500, "Martin Riddle"
martin_... at (no spam) verizon.net> wrote:
http://abcnews.go.com/Blotter/RunawayToyotas/
Maybe I'm missing something, but isn't the obvious solution to drop
the trans into neutral, brake, and turn off the motor?
Yes, almost. Push into neutral, but leave engine running until you
stop (to preserve power steering and brakes... procedure verified on
my daughter's Lexus).
[/quote]
at full trottle there's very little vacuum, but you have vacuum for
one braking, so when you brake mean it.
some toyotas have electric power steering, but the power to it might
be turned of with the engine.
any who, power steering isnt so important at speed
-Lasse |
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| langwadt at (no spam) fonz.dk... |
| Posted: Fri Nov 06, 2009 2:19 pm |
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On 6 Nov., 17:01, ChrisQ <m... at (no spam) devnull.com> wrote:
[quote]Joerg wrote:
Some Volkswagens had that even earlier. A simple governor on top of the
distributor which shorted the whole works if over-revved. Some people
routinely drove them that high and then you could hear the engine cut in
and out really fast, something like 3-5 Hertz.
Same stable, my old 1985 Audi 90 Q was like that, using a spring loaded
rotor arm tip. Modern engines are all electronic though and the
limiting's done in software. Usually with no mechanical override .
Regards,
Chris
[/quote]
but without getting you fingers dirty it can be changed in software.
and without changing things that would already require a remapping why
would you want to change the rev limit?
-Lasse |
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| langwadt at (no spam) fonz.dk... |
| Posted: Fri Nov 06, 2009 2:26 pm |
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On 6 Nov., 01:54, Jim Thompson <To-Email-Use-The-Envelope-I... at (no spam) My-Web-
Site.com> wrote:
[quote]On Thu, 5 Nov 2009 19:45:34 -0500, "Martin Riddle"
martin_... at (no spam) verizon.net> wrote:
http://abcnews.go.com/Blotter/RunawayToyotas/
My #2 Daughter's Lexus has been checked out... push into neutral,
coast to a stop with power-assisted steering and brakes.
I haven't been able to confirm if Toyota's have an RPM limiter to
prevent over-revving and blowing an engine. I know I personally was
designing such electronics clear back in the mid '60's, for Ford, GM
_and_ Chrysler vehicles. Some of those big block V-8's could
otherwise be pushed out to 9-10 kRPM before rods and other debris
issued forth :-(
[/quote]
all recent cars are computer controlled and have rev limiters cutting
injections. with a manual it's not hard to hit the limiter in 1st or
2nd when you drive a little "fresh"
then is it just du-du-du stuttering
-Lasse |
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| who where... |
| Posted: Fri Nov 06, 2009 5:59 pm |
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On Thu, 5 Nov 2009 19:45:34 -0500, "Martin Riddle"
<martin_rid at (no spam) verizon.net> wrote:
[quote]http://abcnews.go.com/Blotter/RunawayToyotas/
[/quote]
Maybe I'm missing something, but isn't the obvious solution to drop
the trans into neutral, brake, and turn off the motor? |
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| Jim Thompson... |
| Posted: Fri Nov 06, 2009 6:08 pm |
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Guest
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On Sat, 07 Nov 2009 06:59:05 +0800, who where <noone at (no spam) home.net> wrote:
[quote]On Thu, 5 Nov 2009 19:45:34 -0500, "Martin Riddle"
martin_rid at (no spam) verizon.net> wrote:
http://abcnews.go.com/Blotter/RunawayToyotas/
Maybe I'm missing something, but isn't the obvious solution to drop
the trans into neutral, brake, and turn off the motor?
[/quote]
Yes, almost. Push into neutral, but leave engine running until you
stop (to preserve power steering and brakes... procedure verified on
my daughter's Lexus).
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Obama says, "I AM NOT a cry baby, Fox REALLY IS out to get me!" |
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| RFI-EMI-GUY... |
| Posted: Sun Nov 08, 2009 12:38 am |
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Martin Riddle wrote:
[quote]http://abcnews.go.com/Blotter/RunawayToyotas/
I see a demand for aftermarket "kill switches".[/quote]
--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©
"Use only Genuine Interocitor Parts" Tom Servo ;-P |
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| ChrisQ... |
| Posted: Mon Nov 09, 2009 4:22 am |
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langwadt at (no spam) fonz.dk wrote:
[quote]
but without getting you fingers dirty it can be changed in software.
and without changing things that would already require a remapping why
would you want to change the rev limit?
-Lasse
[/quote]
I'm not saying that I would. Not a criticism of software either, but any
failsafe system should be partitioned and unrelated to the software to
avoid single point of failure.
Problem is that most modern cars don't have a mechanical distributor any
more, so software is the only place that it can be done unless the
electronics is duplicated and has a separate path to inhibit the
ignition control...
Regards,
Chris |
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| langwadt at (no spam) fonz.dk... |
| Posted: Mon Nov 09, 2009 6:58 am |
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On 9 Nov., 16:09, Jim Thompson <To-Email-Use-The-Envelope-I... at (no spam) My-Web-
Site.com> wrote:
[quote]On Mon, 09 Nov 2009 09:22:52 +0000, ChrisQ <m... at (no spam) devnull.com> wrote:
langw... at (no spam) fonz.dk wrote:
but without getting you fingers dirty it can be changed in software.
and without changing things that would already require a remapping why
would you want to change the rev limit?
-Lasse
I'm not saying that I would. Not a criticism of software either, but any
failsafe system should be partitioned and unrelated to the software to
avoid single point of failure.
Problem is that most modern cars don't have a mechanical distributor any
more, so software is the only place that it can be done unless the
electronics is duplicated and has a separate path to inhibit the
ignition control...
Regards,
Chris
I'm with you. The "safety" path should be distinct from the ECU.
Unfortunately car manufacture is driven "on the cheap"
[/quote]
stuff like that is just more things that can break, if the ecu has
gone to lala land
and can't do rev limiting, theres not much chance it can calculate and
fire the
ignition coils and injectors with the right timing.
the ECU has a watchdog that will reset it something like that
happends.
and normally the ignition coils are powered from a supply switched by
the ignition
key (KL15 I think in bosch speak)
-Lasse |
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| Jim Thompson... |
| Posted: Mon Nov 09, 2009 10:09 am |
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On Mon, 09 Nov 2009 09:22:52 +0000, ChrisQ <meru at (no spam) devnull.com> wrote:
[quote]langwadt at (no spam) fonz.dk wrote:
but without getting you fingers dirty it can be changed in software.
and without changing things that would already require a remapping why
would you want to change the rev limit?
-Lasse
I'm not saying that I would. Not a criticism of software either, but any
failsafe system should be partitioned and unrelated to the software to
avoid single point of failure.
Problem is that most modern cars don't have a mechanical distributor any
more, so software is the only place that it can be done unless the
electronics is duplicated and has a separate path to inhibit the
ignition control...
Regards,
Chris
[/quote]
I'm with you. The "safety" path should be distinct from the ECU.
Unfortunately car manufacture is driven "on the cheap" :-(
BTW, I'm the one who invented the term "limp home". GM (IIRC, at one
point in time I designed for Ford, GM, Chrysler and American Motors
simultaneously) wanted my ignition system to die if the "advance" wire
fell off. I refused to play, and forced a fall-back to default
timing... "limp home"
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
Obama says, "I AM NOT a cry baby, Fox REALLY IS out to get me!" |
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