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Toyota Pedal Issue Highlights Move To Electronics
cyclocommuter writes with an excerpt from a brief WSJ story on increasing electronic control of car components: "The gas pedal system used Toyota Motor Co.'s recall crisis was born from a movement in the auto industry to rely more on electronics to carry out a vehicle's most critical functions. The intricacy of such systems, which replace hoses and hydraulic fluid with computer chips and electrical sensors, has been a focus as Toyota struggled to find the cause for sudden acceleration of vehicles that led the company to halt sales of eight models this week."
Summary is stupid because there's no hoses and hydraulics in any car throttle system I've seen; if it's not electronic, it's a very simple and reliable steel cable.
Story is stupid because as it admits, the electronics had nothing to do with the problem; the failure was mechanical. The exact same thing could have happened to a cable-operated system.
By all accounts I can find, the issue with the Toyota's sticky gas pedal is a MECHANICAL one - not some electrical bug.
-Bill
According to AutoBlog, the problem with these Toyotas is a mechanical part in the drive by wire pedal assembly (and so it's not really an issue with the car being drive by wire). The pivot point that the pedal rotates on has a bushing that is apparently wearing out and causing the pedal stick. I'm a little skeptical as it seems much more plausible that it would be an electrical (or software) gremlin, but that's apparently what they're blaming it on.
There is still no excuse for Toyota not coding the ECU to cut throttle when it senses that the driver has BOTH the throttle and the brakes on simultaneously. All drive by wire VW/Audis are setup this way.
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The latest defect in Toyota cars is quickly developing into the scandal of the 21st century. The problem started when customers of Toyota vehicles began experiencing sudden unexplained acceleration; these incidents began appearing in 2002. Over time, Toyota management claimed that the problem is the floor mat. So, the management issued a recall to replace all the floor mats.
Then, after further studying the problem, the management claimed that the throttle's pedal sometimes becomes stuck due to weather conditions. This new claim lead to the massive global recall of many vehicles sold over the past 3 years.
However, none of these explanations for the sudden acceleration has been satisfactory. Independent investigations leading to an explosion of lawsuits have determined that the problem is the electronic throttle control (ETC) — the so-called drive-by-wire mechanism that links the pedal via some cables to the fuel controller. According to a report by "Businessweek" and another report by the "Wall Street Journal", Toyota is now the defendant in 3 separate class-action lawsuits. The plaintiffs claim that the ETC is defective.
According to a report by the "New York Times" (NYT), "a few years ago, the company sent out a technical bulletin saying some cars accelerate on their own between 38 and 42 mph, and it reprogrammed the electronics with new software codes".
The NYT notes, "John Heywood, director of the Sloan Automotive Lab at MIT, said because Toyota is the only automaker having this problem, it could be something specific to its design, such as the location and integration of the electronics relay sensor."
Further, the Toyota ETC lacks an important safety mechanism: if the customer presses both the throttle pedal and the brake pedal, then the ETC should give priority to the brake. The Toyota ETC gives priority to the throttle. How can Toyota engineers commit such a gross design mistake? Common sense tells us that the brake should receive priority.
I've been around the long-haul trucking business for decades, and I hate to break it to you, but for well over 10 years now, big rigs have had electronic throttle position sensors, with a little bitty, not even particularly well-protected wire running from the pedal to the engine ECM. This is ever since Detroit Diesel came out with their electronically controlled engine in the '90s which was an amazing breakthrough in mileage and reliability. So basically every truck that we've bought or ran for over ten years has had an electronic throttle pedal, and there have been zero problems, except occasionally the TPS itself needs replaced (like every million miles or so). In this case it looks like Toyota fucked up, but that doesn't mean using electronic controls is a bad way to go, because clearly lots of things seem to be able to implement them properly, including airplanes.
1992 - 1995 Isuzu Trooper recall for accelerator cable stuck causing uncontrolled acceleration
2003 Ford Escape stuck throttle cables result in uncontrolled acceleration
2002 Ford Explorers investigated for stuck throttle cables in cold weather regions
1999 - 2004 Suzuki Grand Vitara, recalled due to fraying accelerator cables that result in uncontrolled acceleration and potential crash.
I guess we need to go back to the tried and true horse and buggy as these cable controls do not have a good history of reliability. But we may need to investigate the buggy brakes to ensure the can overpower the horses.
I'm not sure what happened in your bucking Bronco but O2 sensors do not control throttle position, worst case scenario would be an oscillating idle RPM as the computer adjusted fuel mixture from lean to rich. As long as your not touching the accelerator its not going to accelerate uncontrollably and will simply run like shit.
The 'emergency' brake isn't. It's a parking brake. All car literature today refers to it as such. Pull up on your parking brake with your foot held steady at 70 MPH, you won't be slowing down (You will burn up your brakes).
It's there for parking.
This is a worthless story trying to bash electronics for a mechanical failure, and even the story admits that the electronics are not the problem in this specific case. What a load of hogwash. The article doesn't even mention or link to the real source of the problem and it fails to provide additional sources of information for people who might be affected. Someone's got to kick timothy in the ass for getting this dribble posted on the front page. At least post a story about a real electronics's failure causing serious problems such as the O2 sensor issue that the poster above mentioned, now that's a scary situation.
Our New Car
I just bought a 2010 Toyota Camry LE 2.5L I4 6-speed Automatic with EX (Upgraded Radio) and QA (Aluminum Wheels) as a first car for my wife and I as we have just moved across the country to a new city. This was the choice after a lot of researching and test driving of other vehicles and then eliminating them based on real cost of ownership, fuel efficiency, components used, safety ratings, the quality of built, the comfort of the ride, and the headaches or having to deal with the specific sales people (Honda, I'm looking at you!).
Just to make it clear that I'm not a Toyota fan boy and I am not a car person at all since don't find cars "sexy" and I was perfectly happy with my old 1994 Chrysler. This new car is not the perfect vehicle for us, it was just the best in the class for the price. There are some deficiencies in the car, such as the trip computer not showing you fuel efficiency ratings, the quality of the construction in the plastic covering under the engine, cheap plywood backing covering the spare tire in the trunk, and louder than normal wind noise coming from the front roof support posts and root during 80 mpg highway driving speeds, a cup holder divider that comes out anytime you take a cup out of it, and probably a bunch of other issues that we'll find out after more than 4-weeks of owning it.
This recall does not really trouble us since it is mentioned that the issue is rare, it only happens in cars sued for a while already, there is a environmental and humidity aspect to the problem with regards to condensation, and the cause is a gradual wearing down of a bushing that causes additional friction preventing the accelerator pedal from returning back to the home position that happens overtime and is noticeable with a pedal that starts becoming slow to return.
Our car was just manufactured in 2009-11 in Kentucky and I'll be checking the information below today on the weekend to see if our pedal is in the recall or not, most likely it it because it most likely has the CTS manufactured part. I'll call the dealer and arrange for a replacement in a few weeks while after they get a handle on all the people that are coming to them now. No rush on this. I've also instructed my wife on how to resolve this problem if it does occur to her when she's driving by hitting the breaks and shifting into neutral gear, then turning the ignition off when she's safely off the road.
Below is some real information about this recall.
Toyota.com - Latest News About Toyota's Safety Recall Campaign
It would not stop you if you put your foot on the main brake pedal, either. The brakes in cars aren't designed to overcome the engine.
What? Please don't make sarcastic jokes that people might believe. There are people whom, crazily enough, believe that to be true.
There is not a car on the road today that doesn't have higher power brakes than engine. The ratio is beyond ridiculous for smaller cars... my little ancient saturn accelerates at barely 120 HP yet brakes at something near 600 HP.
Its the rare car indeed that takes more than a hundred or so feet to stop from HWY speeds, yet can accelerate to highway speeds in less than a hundred feet or so.
The final test, if you own an automatic transmission car, on the highway, push the accelerator and brake as hard as you can and see what happens. Guaranteed you make an extremely quick stop. Alternately, at a stop sign, all teenage boys get the idea of pushing the brakes and accelerator at the same time, to rev the engine up and squeal the tires when the brakes are released, this tends to overheat the transmission if done on a regular basis. Also it wears the tires out rather quickly.
I once drove a rental manual transmission car, and failed to completely release the parking brake. I'd never heard of one where you have to hold the release button for a second or two, I had only driven cars there you just kind of stab at the button and the parking brake instantly fully releases. Anyway, every time I'd try to get moving, the engine would stall. Even if I floor it while releasing the clutch, the wimpy parking brake left about one tenth actuated on, stalled the engine each time. Everyone accidentally does something like this at one point or another in their manual transmission driving education.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Hint, hint: it may have something to do with the fact that in the US one absolutely needs a car in order to get to work. Few people in Europe work 60km from home, but in the US it is common. Not giving license to someone means literally preventing them from earning a living. Don't pass judgment before understanding the issues. That said, I am a superior driver myself, like everyone on Slashdot, I am sure. My car has 18 gears and 3 clutches - that is because I am so manly. (I also have 3 penises).
They did a test on 3 separate cars, Toyota Camry, Infiniti G37, and Roush Stage 3 Mustang to see the effective stopping power brakes at 70 mph and 100 mph, and each with no throttle and each with full throttle.
Only the Roush Mustang 3 had any real issue of slowing down with full throttle - but only at 100mph. It did stop eventually, but took 903 feet (vs about 320 feet with no throttle).
In the 100mph full throttle tests, the Camry stopped within 88 feet (vs no throttle), the Infinti within 6 feet (The Infiniti has a system that as soon as brakes get tapped the throttle closes, hence such close numbers)
So yes, for 99% of the cars on road, your brakes will overcome your engine easily.
Car and Driver tested just that scenario. At 70 mph and the accelerator floored, a 268 hp Camry came to a full stop in 190 feet (vs 174 feet with no accelerator). It was actually better than a Ford Taurus with no accelerator. So making a controlled stop at full throttle while at speed is very reasonable.
I had a similar experience as you (passenger shoved a windshield heat reflector to my side without me noticing, and it restricted the accelerator's travel so it was half-depressed while I braked). I didn't notice any difference in braking at speed. It was only when I was close to stopped that I noticed it was taking longer than usual to come to a complete stop with the brake depressed the usual amount. So my experience says it just feels a lot worse than it really is. By the time you can feel it, you're traveling slow enough that it while it may take more time to stop completely, it won't take much more distance.