Aces High Bulletin Board
General Forums => The O' Club => Topic started by: Beefcake on March 08, 2010, 05:53:17 PM
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Here is my question: On the new cars do the brake and gas pedals actually connect to the engine / brake cylinders? Or do they connect to a computer that in turn commands the gas/brake?
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I'm wondering the same thing. Personally I believe a Drive-by-Wire system is connected to the brake and accelerator.
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From the ones i've seen, they have a throttle cable and fluid running the brakes like most all cars. I'm thinking the computer is telling the throttle position sensor to accelerate. The brakes are anti-lock and will have wiring involved in that. I'm almost convinced Toyota has a computer problem. Not faulty floor mats or pedals.
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Here is my question: On the new cars do the brake and gas pedals actually connect to the engine / brake cylinders? Or do they connect to a computer that in turn commands the gas/brake?
Drive by wire throttle is purely electrical (sensor based), with no mechanical link to the engine from the pedal.
Some manufacturers feature an E-Safe system. IE: Above a certain speed, stepping on the brake pedal bypasses the computer and sets engine speed to idle. Toyota doesn't offer that on most of the their car and truck line.
Brakes will always be operated by driver input as the primary input. However, various brake assist systems supplement driver input. Should the computer fail, you'll still have brakes, without ABS enabled.
My regards,
Widewing
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From the ones i've seen, they have a throttle cable and fluid running the brakes like most all cars. I'm thinking the computer is telling the throttle position sensor to accelerate. The brakes are anti-lock and will have wiring involved in that. I'm almost convinced Toyota has a computer problem. Not faulty floor mats or pedals.
I believe this has been shown to be the case,of course Toyota says the tests weren't "realistic".
I dont think toyota uses a drive by wire system for throttle or brakes,but most modern fuel injection systems the throttle only controls the airflow and the computer determines the amount of fuel to add!
I'm sure the more mechanicaly inclined will have more to add to this of course.
:salute
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My father and I were having a conversation talking about how older cars are safer, and how these new cars you can't trust since we don't have direct control over the pedals. We weren't sure if the driver had a "direct" connection to the engine or not.
Awhile back I noticed my brake pedal on my old 1998 dodge ram was feeling "odd" and it caused me to check it out. Turns out I had a leak around the master cylinder which led me to replacing it due to it's age. I could feel my brakes weren't "right" just by the way the pedal was acting when pushed. I'm afraid on these cars you wouldn't feel that until it's to late.
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The ones having the problems are all sensor based, no wire or mechanical linkage what so ever. I'll take my caveman car with cables and push rods and be happy.
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The V6 in my 2006 RAV4 is the same basic 3.5 block that's used across the Toyota and Lexus range. Throttle is electronic, brake isn't but (like most cars these days) has ABS and stability control systems.
I've owned three different Toyotas and if they actually made a car I was interested in right now, I quite happily go out and buy another tomorrow.
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My father and I were having a conversation talking about how older cars are safer, and how these new cars you can't trust since we don't have direct control over the pedals. We weren't sure if the driver had a "direct" connection to the engine or not.
Awhile back I noticed my brake pedal on my old 1998 dodge ram was feeling "odd" and it caused me to check it out. Turns out I had a leak around the master cylinder which led me to replacing it due to it's age. I could feel my brakes weren't "right" just by the way the pedal was acting when pushed. I'm afraid on these cars you wouldn't feel that until it's to late.
Absolutely true. We encountered a similar problem which could have resulted in brake failure. We've got ABS, like most modern vehicles. Pedals were operating just fine, vehicle was slowing just fine, except the Brake light was illuminated. Looked under the hood to find the master brake cylinder empty. It's absolutely ridiculous how little feedback there is for the driver. In some cases, I'm sure the lack of feedback has resulted in serious injury or death.
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The brake light was on, the sensor did what is was supposed to and alerted you to a problem.
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Yes, but it came on plenty of times before and we detected no problems (yes, we checked everything). The fact of the matter is, if the brake light comes on whenever it pleases, people will be inclined to ignore it. Therefore I find brake pedal feedback (such as sluggish response) combined with brake light illumination to be a greater indicator than only the brake light illuminating. If we didn't stay vigilant and check our system every time the light came on, we would have ignored the situation and plowed into something (or perhaps someone). ABS is great, yet its feedback lacks.
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The ones having the problems are all sensor based, no wire or mechanical linkage what so ever. I'll take my caveman car with cables and push rods and be happy.
As we all know, cables never fail :lol
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All cars, equipped with some type of electronic traction control system, will have a computer controlled throttle with no direct physical connection to the gas pedal. It has been that way for years.
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All cars, equipped with some type of electronic traction control system, will have a computer controlled throttle with no direct physical connection to the gas pedal. It has been that way for years.
Skuzzy, this is not really the case...
For instance my 00' Grand Am has traction control, it has a standard cable linkage as well. Most of Pontiac's other offerings had the same feature, as well as hundreds of other vehicles. They use timing and dropping spark/fuel to certain cylinders to prevent or control wheel spin. It is true that many of the higher end sports cars with traction control will be as you described though.
Strip
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As we all know, cables never fail :lol
maybe but a cell signal phone isn't going to make a cable flip out.
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Skuzzy, this is not really the case...
For instance my 00' Grand Am has traction control, it has a standard cable linkage as well. Most of Pontiac's other offerings had the same feature, as well as hundreds of other vehicles. They use timing and dropping spark/fuel to certain cylinders to prevent or control wheel spin. It is true that many of the higher end sports cars with traction control will be as you described though.
Strip
Then I stand corrected. I have never worked on a car with an eletronic traction control system which had a physical cable attachment to the gas pedal.
Heck, even a Mini has a fly-by-wire throttle control.
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maybe but a cell single phone isn't going to make a cable flip out.
It wont make a electric throttle control system flip out either....
Strip
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maybe but a cell signal phone isn't going to make a cable flip out.
A cell phone wont make anything flip out. Does your car flip out every time you get a call? Let me guess, you are using string and a can cause its more reliable than the electronic cell phone?
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that was almost funny, but I'm not going doubt some sort of electrical interference might be a cause.
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I'm so glad I drive a caveman truck, I'll take my stick shifter 4L-N-2H-4H over those traction control systems any day.
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Just saw a video online about a guy in Cali that has a Prius, and got a recall letter, he took it in and they told him he wasn't on the recall list, a week later on the highway the gas got stuck, he was going 94mph, CHP had to get in front of him and on a incline was able to stop the car with his.
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I'm so glad I drive a caveman truck, I'll take my stick shifter 4L-N-2H-4H over those traction control systems any day.
My Z/28 has a traction control but still has the throttle cable and the auto stick is still connect directly to the transmission, these Toyota's are all drive by wire. Which is why i think there is an electrical interference some where since the shifting in to Neutral does nothing once the car takes off.
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Toyota, Honda, Infiniti, Lexus, Nissan, Mini, Volvo, Audi, Mercedes Benz, BMW and many others all have drive-by-wire throttles. The reason many of them have it is due to how the fuel and air are being regulated today.
Mini and BMW use dynamic valve trains (lift and duration) to regulate the flow of air into the engine, in combination with varying the pulse width of the eletronic injector. How are you going to hook up a cable to that?
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Mechanical linkage can fail too. I had a '75 F250 with a 390 in it when you mashed the go pedal down hard the engine would go full throttle and stay there until you shut off the ignition. Later found that the two bolts that hold the driver side motor mount to the frame had backed out and was allowing the motor to lift up. It wasn't a problem under part throttle but made for a few exciting experiences when the gas was mashed.
Ford has been using a drive-by-wire throttle on their PowerJoke diesel since '94.
Funny thing is these are pretty much the same comments heard when the F-16 was introduced.
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Toyota, Honda, Infiniti, Lexus, Nissan, Mini, Volvo, Audi, Mercedes Benz, BMW and many others all have drive-by-wire throttles. The reason many of them have it is due to how the fuel and air are being regulated today.
Mini and BMW use dynamic valve trains (lift and duration) to regulate the flow of air into the engine, in combination with varying the pulse width of the eletronic injector. How are you going to hook up a cable to that?
Difference there is I trust Mercedes Benz, BMW and few of the others.
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You are talking about Mercedes Benz who decided not to use a head-light relay on some of its late model cars which resulted in switches burning out? The damage would not be localized to just the switch either.
You talking about BMW who decided plastic would be a good material to use for a thermostat housing, which turns out, would disintegrate at almost precisely 50,000 miles and take the engine with it? Or how about iDrive?
Every car company has some skeletons in the closet.
And again, how do you cable an electronically controlled fuel injector or dynamic valve train operations?
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I've gone back read my posts and all i said is "I'll take my caveman car with cables and push rods and be happy." not once saying they need to hook cables to ever car on the planet. curious where you got that from?
on the side I'm sure one day I'll be in a car that has the same system, just won't be a Toyota.
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And again, how do you cable an electronically controlled fuel injector or dynamic valve train operations?
I think people are getting a little confused because they see a cable that leads to the throttle. The fact that the computer reads the throttle position sensor and mass air flow sensor and makes the required adjustments to the engine is not so easily seen.
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Ok I will admit my brakes or throttle cables could easily break/fail on my old caveman car. However, unless it's a catastrophic failure you can usually feel/hear these problems long before they reach a critical point.
The reason why I don't want a computer controlling my brakes / gas is simple, look at computers today. My desktop will sometimes randomly crash, for no reason, and upon recovery the computer doesn't even know it crashed. A car's computer is no different and I don't trust windows controlling my brakes. I'm just not comfortable with the possibility that my cars computer might BSOD and in turn cause me to suffer a WOD because the gas pedal stuck.
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You are talking about Mercedes Benz who decided not to use a head-light relay on some of its late model cars which resulted in switches burning out? The damage would not be localized to just the switch either.
You talking about BMW who decided plastic would be a good material to use for a thermostat housing, which turns out, would disintegrate at almost precisely 50,000 miles and take the engine with it? Or how about iDrive?
Every car company has some skeletons in the closet.
And again, how do you cable an electronically controlled fuel injector or dynamic valve train operations?
True, i remember we were replacing axillary fans on X5, after few vehicles caught on fire they issued recall.Actually BMW doesn't make thermostats, BEHR does. When it fails BEHR pays labor and for loaner vehicle if needed plus you get 2 year warranty for every BMW part after replacement. And the only reason it takes engine with it is because for some reason people choose to ignore bright red overheat warning light or cover temperature gauge with picture of family members.
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OK guys... First off, I am an ASE Certified Master Technician with over 15 years in automotive repair.
Yes MOST cars built today do in fact have NO mechanical connection between the throttle pedal and the engine. In the old days, a cable connected the gas pedal to a valve that controls how much air enters the engine. The computer of a typical fuel injected system would detect this by a throttle position sensor at the air valve at the engine, and an airflow sensor (or a pressure sensor, or both) and would command the fuel injectors to stay open longer to add more fuel, allowing the engine to 'rev up'. There was a separate air valve (often called a idle control valve) that was electrically controlled that would allow air to flow around the mechanical valve so the computer could control engine idle speed... to compensate for temperature, engine loads (A/C compressor, Power steering, high electrical loads, etc), and driving conditions.
On Most cars built today, instead of a mechanical air valve, it is controlled electrically by the computer with an electrical motor. This 'simplifies' things a bit as the idle control valve can be eliminated. The air valve is under a heavy spring load that the electric motor has to overcome so in the event of just about any failure, the computer would simply kill voltage going to this motor, and the air valve would simply spring shut. Basically, the engine would likely continue to idle but depressing the gas pedal would result in nothing happening.
There is still a throttle position sensor at the air valve at the engine, but there are also two throttle position sensors built into the gas pedal assembly. The computer uses the two in the gas pedal for redundancy purposes, and it uses the sensor at the air valve to make sure the electric motor is moving the valve to the proper position. If the two pedal sensors don't read the same, the computer sets a fault code (check engine light) and will uses the lower input of the two. If the computer sees a failure of the engine sensor (or the circuit for the throttle motor), it sets a fault code AND goes into a 'limp mode' of sorts which basically disables the throttle.
This makes it almost IMPOSSIBLE for the electrical system to malfunction in a way that the throttle valve at the engine would stay in the open position.
Now, here's the problem with the Toyota systems. The Gas pedal assembly has an amount of built in mechanical resistance built in to it, to make it feel almost identical to the older cars which had resistance in the pedal due to the cable and mechanical valve. What is happening is the pivot point of the pedal is wearing down a bit, and the resistance 'plate' rubs the pedal too hard, making it physically stick in a downward position. Imagine your joystick... if you spilled a soda on it and it got all gummed up so bad that it would hang up on the gunk so much the spring couldn't pull it back to center. Same basic thing.
Since the Pedal is sticking mechanically, the sensors all read properly and the computer actually thinks you're pressing down on the gas pedal.
The fix is to install a shim into the pedal assembly to push the resistance plate further away from the moving parts of the pedal, to compensate for the wear in the hinges.
Skuzzy is incorrect about traction control never having a mechanical connection. Even if you hold the air valve open mechanically, the computer can still kill the injectors, or the coils to prevent the engine from running, or to reduce its power.
Skuzzy is however right about every manufacturer having skeletons in their closets. I probably don't need to mention the Pintos.. or the 2.6L Mitsubishi engines in the first generation Caravans... Or the Ford Probe... Or the plastic intakes on the Ford 4.6L... or the plastic intake gaskets on the GM 3.1L, 3.4L, 4.3L, 5.7L... or maybe even Dexcool (known in the industry as 'death-cool') antifreeze. Neon Head Gaskets? How about the Ford trucks massive cruise control switch recall... and then the recall on their recall... that recall which was revised over 17 (yes that's SEVENTEEN times) because the harness that installed a fuse into an unfused circuit, had the fuse on the GROUND SIDE of the circuit for some models... Anyway.. I could go on and on and on. And yes imports are NOT exempt from these sorts of things either...
Regardless, with this being said, should your car even continue to accelerate after you take your foot off the gas, there ARE things you can do. If it is a stick shift, you can always depress the clutch. In an automatic, you can always move the shifter to neutral. In either case, you can simply turn off the key (or if no key, push and hold the START/STOP button).
I just had a heated debate with my g/f a couple hours ago about this. She said that she had no idea one could turn off the engine while driving the car. I asked her if she ever read the owner's manual for her car. She said 'no'. It really amazes me how people will spend hours studying the manual for a $25 piece of electronic junk (or a $300 Joystick.. you get the point), but when it comes to a $20,000+ vehicle, most people never even look at the cover. Yes it's very easy to blame the manufacturers for accidents resulting in malfunctions such as this, however if people would take even a few minutes to learn about these machines that they are trusting their own lives (and the lives of their families) to, then the VAST MAJORITY of these accidents could be easily avoided.
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Thanks for the info Tigger, that really explained alot!
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Trigger in case of the Cali guy yesterday he said putting the car into neutral didn't not slow the car down, it kept going. I've heard that's the case in all these, shifting to N has done nothing, is it possible for that piece to cause that also or can these cars not shift to N while at high speeds? I know nothing about the Prius since i have zero interest in the car but would think any car could shift to N.
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so turning the car off would disengage the accelerator.
will the brakes work then? (foot and/or hand brakes)
i'm guessing power steering will also be lost when the car is turned off,
but that will only come into play once the car is running at 5MPH before it starts to feel "heavy."
thanks tigger.
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My Z/28 has a traction control but still has the throttle cable and the auto stick is still connect directly to the transmission, these Toyota's are all drive by wire. Which is why i think there is an electrical interference some where since the shifting in to Neutral does nothing once the car takes off.
I would bet on a software bug or a faulty sensor before I'd put any money on anything else. There is something wrong with the model that they wont admit but will get fixed in the new version without any one knowing. Hmmmmm :lol
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Here is my question: On the new cars do the brake and gas pedals actually connect to the engine / brake cylinders? Or do they connect to a computer that in turn commands the gas/brake?
some newer cars don't have a direct throttle linkage. some gm's....namely the firechicken....have had throttle by wire since the late 90's.
i just had a cadi cts with throttle by wire.
to the best of my knowledge, there is still direct hydraulic link to the brakes, although much of that is controlled through various computers, through the use of solenoids.
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Drive by wire throttle is purely electrical (sensor based), with no mechanical link to the engine from the pedal.
Some manufacturers feature an E-Safe system. IE: Above a certain speed, stepping on the brake pedal bypasses the computer and sets engine speed to idle. Toyota doesn't offer that on most of the their car and truck line.
Brakes will always be operated by driver input as the primary input. However, various brake assist systems supplement driver input. Should the computer fail, you'll still have brakes, without ABS enabled.
My regards,
Widewing
there;s some working on "dry" braking systems. basically a master cylinder on each strut, and an electric motor to actuate the caliper through those cylinders.......but no direct mechanical linkage.
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Absolutely true. We encountered a similar problem which could have resulted in brake failure. We've got ABS, like most modern vehicles. Pedals were operating just fine, vehicle was slowing just fine, except the Brake light was illuminated. Looked under the hood to find the master brake cylinder empty. It's absolutely ridiculous how little feedback there is for the driver. In some cases, I'm sure the lack of feedback has resulted in serious injury or death.
what kind of car?
if the master was empty, you had a leak(which should've been noticed by a sinking/mushy pedal) or your pads were fully worn out, and all the fluid was in your calipers.....in which case you should've had a squealing as the wear indicators hit the rotors.
brake fluid doesn't evaporate.
it's not a lack of feedback....,.....you just need to "listen:" to the little things your car tells you. and your car is ALWAYS talking to you. :aok
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Yes, but it came on plenty of times before and we detected no problems (yes, we checked everything). The fact of the matter is, if the brake light comes on whenever it pleases, people will be inclined to ignore it. Therefore I find brake pedal feedback (such as sluggish response) combined with brake light illumination to be a greater indicator than only the brake light illuminating. If we didn't stay vigilant and check our system every time the light came on, we would have ignored the situation and plowed into something (or perhaps someone). ABS is great, yet its feedback lacks.
when it was going on n off, the fluid was low, and tripping the sensor under certain conditions.
if your shop never explained this to you, you should consider looking for a new place to have your car serviced.
part of our job(in my opinion) is to educate our customers about their cars.
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All cars, equipped with some type of electronic traction control system, will have a computer controlled throttle with no direct physical connection to the gas pedal. It has been that way for years.
early ones still had throttle cables.
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A cell phone wont make anything flip out. Does your car flip out every time you get a call? Let me guess, you are using string and a can cause its more reliable than the electronic cell phone?
believe it or not, some of the "speed pay" systems at gas stations used to seriously screw with the security computers on chrysler products.
i\
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I have to agree with this 100%:
Yes it's very easy to blame the manufacturers for accidents resulting in malfunctions such as this, however if people would take even a few minutes to learn about these machines that they are trusting their own lives (and the lives of their families) to, then the VAST MAJORITY of these accidents could be easily avoided.
In the cases where shifting to n does nothing, its time to shut off the vehicle. You will loose power assist on brakes and steering but you will still be able to control the car.
The ratio of intelligence to litigation in this country is getting out of hand.
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I have to agree with this 100%:
In the cases where shifting to n does nothing, its time to shut off the vehicle. You will loose power assist on brakes and steering but you will still be able to control the car.
The ratio of intelligence to litigation in this country is getting out of hand.
yea it is. i've not worked on a prius yet, but i'm sure there is some sort of emergency procedure for something like what's happening.
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early ones still had throttle cables.
Yes, I know. I have been corrected by 2 others in the thread already. I should have worded the original response better.
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Yes, I know. I have been corrected by 2 others in the thread already. I should have worded the original response better.
yea......my apologies on that sir.....i should've read down further before i typed that........
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Trigger in case of the Cali guy yesterday he said putting the car into neutral didn't not slow the car down, it kept going. I've heard that's the case in all these, shifting to N has done nothing, is it possible for that piece to cause that also or can these cars not shift to N while at high speeds? I know nothing about the Prius since i have zero interest in the car but would think any car could shift to N.
that's not what he said, he was told to shift to neutral by 911 and the CHP car, he refused, he said he was afraid the car would "flip" if he did that.
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that's not what he said, he was told to shift to neutral by 911 and the CHP car, he refused, he said he was afraid the car would "flip" if he did that.
what i read and video is saw said nothing of that nature, it said that Neutral did nothing in everything i saw.
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when it was going on n off, the fluid was low, and tripping the sensor under certain conditions.
if your shop never explained this to you, you should consider looking for a new place to have your car serviced.
part of our job(in my opinion) is to educate our customers about their cars.
We figured that out upon refilling the brake fluid. The shop didn't explain anything because they didn't find anything.
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We figured that out upon refilling the brake fluid. The shop didn't explain anything because they didn't find anything.
yea.....i was talking to someone else about this kind of stuff.
something that simple, they should've found. i don't like talking bad about anyone else in the business.....but that was basics 101.
i explain everytning i'm doing to pretty much everyone.....men dont like to listen..they like to think they know it all. women, on the other hand, listen very intently, and are always appreciative that one of us takes the time to explain things in terms that they can understand.
if you're taking your car to a dealer, get the hell outta there.......if you're taking it to a franchise, like goodyear, firestone, sts, or any of them, again.,...get the hell outta there.
find yourself a privately owned shop. you'll find that you may have to do some searching, but you'll find a much more knowledgable tech to work on your car.
start with the IATN.net website.
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We assume all the dealership did was hook up their computer to the system. The dealership never communicated with us, yet feel the necessity to charge us premium rates. Yes, we're already looking at local businesses.
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We assume all the dealership did was hook up their computer to the system. The dealership never communicated with us, yet feel the necessity to charge us premium rates. Yes, we're already looking at local businesses.
that's why i don't like dealers.....i could explain...and will later when i have more time to type here.....
but.....
www.iatn.net
or www.napaauto.com
they're both good sources to find decent privately owned shops.
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A Toyota spokesman said Monday evening that the company, which has recalled millions of vehicles because of reports of unintended acceleration, was sending a representative to investigate the cause of the incident.
The cellphone call came about 1:30 p.m. from the driver of the blue 2008 Prius eastbound on Interstate 8 in San Diego County.
"He was driving near the La Posta Indian Reservation when he called 911 and said his gas pedal was stuck," Landeros said.
"I pushed the gas pedal to pass a car and it did something kind of funny . . . it jumped and it just stuck there," Sikes, 61, said at a news conference. "As it was going, I was trying the brakes . . . it wasn't stopping."
A CHP patrol officer caught up to the Prius about 20 minutes later and used a loudspeaker to tell the driver to apply his emergency brake in tandem with the brake pedal, Landeros said.
Once the Prius' speed dropped to about 50 mph, Sikes turned off the engine and was able to coast to a stop, the officer said.
Landeros didn't know why the driver waited until his speed had dropped to turn off the engine, but the officer speculated that Sikes feared losing the car's power steering.
The officer drove in front of Sikes' Prius to block the car if necessary. But the two cars never touched, Landeros said.
No one was hurt, the CHP said.
http://www.latimes.com/business/la-fi-toyota-chp9-2010mar09,0,3699926.story (http://www.latimes.com/business/la-fi-toyota-chp9-2010mar09,0,3699926.story)
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Trigger in case of the Cali guy yesterday he said putting the car into neutral didn't not slow the car down, it kept going. I've heard that's the case in all these, shifting to N has done nothing, is it possible for that piece to cause that also or can these cars not shift to N while at high speeds? I know nothing about the Prius since i have zero interest in the car but would think any car could shift to N.
I was wondering about that from the beginning of this whole thing. Why not shift into neutral?
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Trigger in case of the Cali guy yesterday he said putting the car into neutral didn't not slow the car down, it kept going. I've heard that's the case in all these, shifting to N has done nothing, is it possible for that piece to cause that also or can these cars not shift to N while at high speeds? I know nothing about the Prius since i have zero interest in the car but would think any car could shift to N.
There is almost no reason whatsoever why the vehicle would continue to accelerate after shifting into Neutral unless the computer is somehow programmed to stay in gear electronically to protect the engine.. that would be the only theory I could come up with. Doesn't make much sense, but yet I can see engineers doing such a thing.
I would also have hoped that depressing the brake pedal would override any gas pedal input whatsoever... erring on the side of caution I would say... basically, if both pedal are pressed, the computer would automatically choose to brake over accelerating. Still though, this doesn't seem to be the case.
Perhaps it's because of the few people out there that still ride their brakes by driving with both feet..
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Totally unscientific test. Just tried shifting my RAV4 into neutral doing about 50 on a quiet road. The car did indeed shift into neutral as I intended. Should point out my particular model hasn't been recalled.
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While the real cause of the Toyota unintended acceleration issues are still under investigation by the National Highway Traffic Safety Administration (NHTSA), one news outlet is reporting that they know what's behind it. ABC News tracked down one David Gilbert, an automotive technology professor at Southern Illinois University, who says he knows exactly what it is. According to Gilbert, it's an electronic design flaw in Toyota's 'Fail Safe' system.
Gilbert says the flaw "prevents the car's onboard computer from detecting and stopping certain short circuits that can trigger sudden speed surges." ABC News adds, "he can recreate a short circuit in the electronic throttles of Toyotas that can create a surge of acceleration but can't be detected by Toyota's electronic sensors."
Because the computers won't record an error code in this situation, Gilbert told ABC, "they can't activate the 'fail safe' system designed to shut down the power and put the car in the 'limp home' mode."
If you want to read some more, here's the link:
http://www.autoblog.com/2010/02/22/abc-news-expert-says-electronic-design-flaw-to-blame-in-runaway/4
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Mr. Sikes drove 93 mph? :O
I am driving up to 120 mph each day to work and back home (on the autobahn with my BMW 320i) :D :bolt:
but seriously:
A friend of mine had a similar problem with his VW Polo (with shifting gears). He drove with 80 mph on the autobahn, when suddenly the car went faster. He used both brakes and slowed the car down, shifting the gears down, drove on the far right lane (emergency lane) and stayed on brakes until his car was about to stop. Then he went into neutral and shut down motor when the car stopped.
As driving automatic I guessed going into neutral and staying on the brakes would help. :confused:
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There is almost no reason whatsoever why the vehicle would continue to accelerate after shifting into Neutral unless the computer is somehow programmed to stay in gear electronically to protect the engine.. that would be the only theory I could come up with. Doesn't make much sense, but yet I can see engineers doing such a thing.
I would also have hoped that depressing the brake pedal would override any gas pedal input whatsoever... erring on the side of caution I would say... basically, if both pedal are pressed, the computer would automatically choose to brake over accelerating. Still though, this doesn't seem to be the case.
Perhaps it's because of the few people out there that still ride their brakes by driving with both feet..
i drive with both feet.....and i can assure ya i don't ride the brake. :aok
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Totally unscientific test. Just tried shifting my RAV4 into neutral doing about 50 on a quiet road. The car did indeed shift into neutral as I intended. Should point out my particular model hasn't been recalled.
your rav4 has a mechanical linkage to the tranny
on that note, i just went into my information system.....it seems true that there is no actual shifter linkage on the prius.
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i drive with both feet.....and i can assure ya i don't ride the brake. :aok
I drive with both feet too. I did learn how to heel toe brake when I first learned to drive, and still use the technique in the Mustang. The pedals are not positioned correctly to do so in my truck. Yes they are both manual transmissions. No I don't ride the brake.
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I drive with both feet too. I did learn how to heel toe brake when I first learned to drive, and still use the technique in the Mustang. The pedals are not positioned correctly to do so in my truck. Yes they are both manual transmissions. No I don't ride the brake.
that;s the only thing that pisses me off about my dakota.......the pedals aren't positioned for me to heel/toe. on my fairmont(mustang in disguise) they are perfect.
i meant that i also use both feet when i'm driving something with an automatic too. i've been a left footed braker in automatics for as long as i can remember, :aok
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I only use my right foot in slushbox equipped vehicles, but I keep looking for the clutch with my left. :O
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While it is possible to drive with both feet (YES in an automatic) without riding the brake, it really isn't recommended. Why? Because when things happen, people tend to panic. If you have both feet above both pedals and you panic, it's possible to just mash both of them down without even thinking about it.
I'm not picking anyone out specifically, but the body does funny things sometimes while in panic mode regardless of how well you think you've trained it. The 'best' way to drive IMHO is to use one foot for gas and brake, and anytime you're not accelerating, keep the foot above the brake pedal.
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While it is possible to drive with both feet (YES in an automatic) without riding the brake, it really isn't recommended. Why? Because when things happen, people tend to panic. If you have both feet above both pedals and you panic, it's possible to just mash both of them down without even thinking about it.
I'm not picking anyone out specifically, but the body does funny things sometimes while in panic mode regardless of how well you think you've trained it. The 'best' way to drive IMHO is to use one foot for gas and brake, and anytime you're not accelerating, keep the foot above the brake pedal.
85 chrysler 5th ave....the rear driver.
coming up to the intersection........left foot on the brake, it's stopping, then suddenly the pedal drops to the floor. no biggie.......pump the pedal, yank the shifter into low gear(auto), left foot off the brake onto the e-brake.
was pretty easy actually.
i've been driving like this for 31 years.
if you're accustomed to it, it's much much faster to get your left foot(which is doing nothing normally) onto the brake, rather than release tension on the gas pedal, pick your foot up, then place it on the brake pedal.
would i recommend anyone switch? hell no!! that's how ya get into trouble.
would i train a new driver like that? in a heartbeat.
most of the accidents that come from older people, are generally them pressing on the go pedal, rather than the stop pedal. left footed braking would totally prevent that. :aok
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Why? Because when things happen, people tend to panic.
not all of us panic when bad things happen. Some of us know what to do and do it.
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not all of us panic when bad things happen. Some of us know what to do and do it.
i know i don't.
when the lady hit me head on, rather than panicking, i was trying to get outta her path...almost made it too.
when the kid pitted us, i was still trying to steer the car outta the skid as it hit the curb and went airborne.
when my brakes failed, i successfully and rather easily brought my car to a safe stop.
it's not really hard, IF you really drive your car, rather than being a passenger behind the wheel. :aok
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I'm not picking anyone out specifically,
How did I know this would turn into a whole "I'm such a good driver that never happens" kind of debate? Yes there ARE exceptions to the rule, but you have to admit that this could be a big problem with people in general, which is why it isn't taught that way.
I also highly doubt that you drive with your left foot hovering over the brake pedal all of the time... I'm thinking you rest your left foot next to the brake pedal, which means your response time wouldn't necessarily be any faster.
When I drive customers' cars, I try to hold my feet up off the floor, to minimize any chance of getting any stains.. just a habit I've developed over the years.. and after about 30-60 seconds, it starts to get very uncomfortable.
Regardless, you have to admit that a lot of people who drive with two feet tend to rest their left foot just a little bit on the brake pedal, applying just a little bit of braking force (and yes I've caught several customers riding their brakes after they come back with repeat brake problems). All I was saying is that if Toyota had programmed their cars to ignore gas pedal input if the brake was applied, they'd have a lot of unhappy customers.
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How did I know this would turn into a whole "I'm such a good driver that never happens" kind of debate? Yes there ARE exceptions to the rule, but you have to admit that this could be a big problem with people in general, which is why it isn't taught that way.
I also highly doubt that you drive with your left foot hovering over the brake pedal all of the time... I'm thinking you rest your left foot next to the brake pedal, which means your response time wouldn't necessarily be any faster.
When I drive customers' cars, I try to hold my feet up off the floor, to minimize any chance of getting any stains.. just a habit I've developed over the years.. and after about 30-60 seconds, it starts to get very uncomfortable.
Regardless, you have to admit that a lot of people who drive with two feet tend to rest their left foot just a little bit on the brake pedal, applying just a little bit of braking force (and yes I've caught several customers riding their brakes after they come back with repeat brake problems). All I was saying is that if Toyota had programmed their cars to ignore gas pedal input if the brake was applied, they'd have a lot of unhappy customers.
my grandpop did. i could be following him down the freeway, and see the brake lights goin on n off at 65mph.
i keep my left foot on the "dead pedal". when i'm in customers cars, i use floormats.
i honestly believe that unless we find a way to convince drivers that distractions are bad, it really doesn't matter how they're trained.
eating, while putting on eyeshadow, drinking a cup of coffee, and reading the paper all at once is pretty bad.
i actually saw a lady plucking her eyebrows at a traffic light one time.
driving should be like flying a cessna......no distractions other than those necessary to drive the car safely.
also, as i said....i would not recommend anyone changing to left footed braking, nor would i recommend them trying it. :aok
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i honestly believe that unless we find a way to convince drivers that distractions are bad, it really doesn't matter how they're trained.
driving should be like flying a cessna......no distractions other than those necessary to drive the car safely.
Quoted for truth
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CCN has a video on them unable to recreate the Prius in runaway mode.(they used the car that was involved in the incident)As soon as the brake was applied the engine would shut off.
http://www.cnn.com
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OK looks like the whole "runaway" prius thing may have been staged:
http://www.forbes.com/2010/03/12/toyota-autos-hoax-media-opinions-contributors-michael-fumento.html (http://www.forbes.com/2010/03/12/toyota-autos-hoax-media-opinions-contributors-michael-fumento.html)
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OK looks like the whole "runaway" prius thing may have been staged:
http://www.forbes.com/2010/03/12/toyota-autos-hoax-media-opinions-contributors-michael-fumento.html (http://www.forbes.com/2010/03/12/toyota-autos-hoax-media-opinions-contributors-michael-fumento.html)
yea....saw something about this last week.....
and thanks to our friends the lawyers, everyone's trying to jump on the bandwagon.
you oughtta hear the commercials from law firms around here.