Breaking News
News & Analysis

Acceleration Case: Jury Finds Toyota Liable

10/24/2013 09:00 PM EDT
43 comments
More Related Links
View Comments: Oldest First | Newest First | Threaded View
<<   <   Page 5 / 5
patrick.mannion
User Rank
Staff
Bad month for Toyota: Camry off the CR recommended list
patrick.mannion   10/31/2013 4:17:53 PM
NO RATINGS
It's been a bad month for Toyota: Consumer Reports has just dropped the Camry from its recommended list due to a poor showing in the highway safety institute  crash test

http://live.wsj.com/video/consumer-reports-drops-camry-from-recommended-list/C99B752A-877F-436C-9575-65E99C401CC0.html?KEYWORDS=toyota#!C99B752A-877F-436C-9575-65E99C401CC0

 

Rabbit2
User Rank
Rookie
Re: More to come
Rabbit2   11/2/2013 8:21:14 AM
NO RATINGS
This is true to a degree.  The brakes must be applied firmly to bring the vehicle to a complete stop and stall the engine without delay.  If the brakes are "ridden" to merely reduce or control the vehicle speed, the brakes will fairly quickly overheat and fail due to loss of "coefficient of friction" of the braking material.  Nearly all friction material becomes more slippery as it heats up.  The exception is "metallic" linings used for police and racing use.  Metallic linings become less slippery as they heat up.  These linings are not stocked by common auto parts stores, you have to obtain them through special sources.  I have a vehicle equipped with these - they wear like iron - never wear out.  The down side is that you almost have to be an elephant to stop the car when they are cold - particularly in the winter.  Without power assist (which my equipped car does not have), i suspect that a woman would be incapable of stopping the car with cold brakes.  I am its only driver - so that doesn't matter. 


The other point is that a sudden power application - when you are not expecting it - at a critical time, could cause loss of control.  An example would be suddenly decending a steep exit ramp from a freeway on wet pavement.  You saw the exit sign at the last moment - not knowing the area - and exited at a somewhat higher than prudent speed, but still under control.  Then you discover that the exit ramp has a decreacing radius curve (poor design).  If the vehicle suddenly goes to full throttle at this point - i suspect most drivers (including myself) would be hard pressed to maintain control.  Firm application of the brakes on wet pavement could cause the vehicle to continue straight on - into a retaining wall or other obsticle, rather than tracking a curve.  Cheers.

Rabbit2
User Rank
Rookie
Re: Throttle problem in new Toyotas
Rabbit2   11/2/2013 8:41:09 AM
NO RATINGS
IMHO, this is a common problem in the automotive and software areas.  In 1963, my parents purchased a Chevrolet passenger car with a 6 cylinder engine.  It was not "fly by wire", but had an annoying problem.  When you attempted to hold a steady speed, the vehicle would constantly "buck" - surge forward and back.  We had the new vehicle back to the dealer dozens of times.  Always, the "fix" was just a few days away.  Finally a "special part" was ordered to fix the problem.. It was installed, and the problem was just as bad as ever.  This time however, any acceleration produced dense black smoke from the exhaust.  Additionally, the gas mileage went down by about 8 miles a gallon (that's a LOT).  A high school student at the time - i finally was "allowed" to look at the problem.  I found that the "magic part" consisted of a main metering jet in the carburator that was 7 steps rich.  I replaced it with the standard jet, and mileage returned to normal - but the bucking continued.  After a few weeks of experimenting, i found that the bucking was caused by springs in the distributor that were too weak.  As engine speed increases, it is necessary to advance the spark timing to burn the fuel before it is exhausted.  In the 1963 era, this was done with "bob weights" in the distributor body, which were restrained by small springs.  As the speed increased, centripital acceleration forced the weights outward against spring tension, thereby advancing the spark.  The springs installed by the factory were considerably weaker than they should have been.  NOBODY at the factory had ever put one of these distributors on a distributor machine (common equipment in a "speed shop") to verify that the advance curve was appropriate.  The problem persisted until 1970.  So the vast automotive industry could not solve a problem that a high-school junior solved in 3 or 4 weeks in 7 years.  Don't hold your breath for Toyota to come up with a solution.  Cheers.

<<   <   Page 5 / 5
August Cartoon Caption Winner!
August Cartoon Caption Winner!
"All the King's horses and all the KIng's men gave up on Humpty, so they handed the problem off to Engineering."
5 comments
Top Comments of the Week
Like Us on Facebook

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
EE Times on Twitter
EE Times Twitter Feed
Flash Poll
Radio
NEXT UPCOMING BROADCAST
How to Cope with a Burpy Comet
October 17, 2pm EDT Friday
EE Times Editorial Director Karen Field interviews Andrea Accomazzo, Flight Director for the Rosetta Spacecraft.