Stopping a car with a jammed accelerator

r3nu4l

From BBC

1. Use the footbrake, not the handbrake
2. Depress the clutch
3. Look for a route to the side of the road, and steer there carefully
4. Only switch the engine off if the clutch cannot be used instead
5. If footbrake has failed, you can use very gentle handbrake
Source: Stephen Mead

So it's topical and this is the advice on how to stop a car when the accelerator is jammed.

Looking at point 5 though I began to wonder...what if you have a push-button electronic handbrake? Can't exactly apply it 'gently', it's either on or off.

Do we agree with that advice? Would you change down gears? If you had an electronic handbrake and all else failed would you be in a right jam (pun alert) altogether?

colm_mcm

If it's a manual, then use the clutch. if it's auto put it into neutral.

I would also guess that given it's usually an intermittent fault, stabbing the accellerator might fix it.

Highly unlikely that the footbrake would also fail.

Don't know what advantage changing down gears with the accelerator jammed open would do.

mickdw

r3nu4l wrote: »

From BBC



So it's topical and this is the advice on how to stop a car when the accelerator is jammed.

Looking at point 5 though I began to wonder...what if you have a push-button electronic handbrake? Can't exactly apply it 'gently', it's either on or off.

Do we agree with that advice? Would you change down gears? If you had an electronic handbrake and all else failed would you be in a right jam (pun alert) altogether?

I know with the Vw/Audi electronic handbrakes, they will not jam on at speed, they will just beep. If you do need to use it to stop in an emergency, you must keep the electronic brake button pressed. This then starts an emergency stop procedure which applies light braking to all 4 wheels and brings the car to a stop. The electronic brake is therefore better than the traditional system in this regard.
I think this is an important feature and could be very useful in the situation of where a driver had a heart attack or something. The passenger could very easily stop the car if the handbrake button is on the centre console whereas trying to pull a traditional handbrake will do very little to stop a car at speed.

biko

It really depends on the situation too.
You could just press clutch and coast and brake to the side of the road.
And then switch engine off. If you switch engine off immediately you might rotate key too far and engage steering wheel lock.

mickdw

colm_mcm wrote: »

Don't know what advantage changing down gears with the accelerator jammed open would do.

It would certainly slow you down, but if you have a manual car just clutch the f*ucking thing and let it scream its head off.

jayotala

I'd say engine off and plant foot on the brake.

thebiglad

Magnus wrote: »

It really depends on the situation too.
You could just press clutch and coast and brake to the side of the road.
And then switch engine off. If you switch engine off immediately you might rotate key too far and engage steering wheel lock.

I thought turning the engine off (even if not as far as steering lock position) would diable the power steering?

colm_mcm

thebiglad wrote: »

I thought turning the engine off (even if not as far as steering lock position) would diable the power steering?

Not really an issue unless you're parking.

biko

Yes that too but a strong guy like you or me could still drive it.
I've had engines conk out on me in corners and still I could steer.

thebiglad

jayotala wrote: »

I'd say engine off and plant foot on the brake. All this because Toyota launched a recall... mountain out of a mole hill if ya ask me.

Tell that to the relatives of the Lexus occupants in US which sparked this recall.

If Toyota did not think there was something to it then they would not spend immense amounts on a recall, not to mention the bad publicity.

TouchingVirus

colm_mcm wrote: »

Not really an issue unless you're parking.

Are you serious? Every car I've ever been in that had power steering and lost power ended up being incredibly tough (by comparison) to steer without it. This could surprise many a driver if they just aren't thinking right given the situation.

It is much, much safer to coast on the clutch if you can and turn on the hazards to alert other drivers to your problem.

peasant

Happened to me the other day (accelerator cable frozen in its sleeve, since fixed) and the only advice that I can give is to get into neutral and stop as fast and as decisively as you can.

In my case there was nowhere to stop and I had to negotiate a dual carriageway off-ramp and a roundabout, alternating between clutching/braking/accelerating and by the time I finally could stop, the brakes were nice and warm and starting to fade ...a bit longer and I probably wouldn't have stopped at all ...not in a controlled way, anyway.

peasant

thebiglad wrote: »

I thought turning the engine off (even if not as far as steering lock position) would diable the power steering?

more importantly, it also leaves you without brake servo ...which means you will have to push the brakes REALLY hard (pulling out the steering wheel hard) in order to stop. Not a lot of people would be used to doing this.

jayotala

thebiglad wrote: »

Tell that to the relatives of the Lexus occupants in US which sparked this recall.

If Toyota did not think there was something to it then they would not spend immense amounts on a recall, not to mention the bad publicity.

Yeah, sorry I have to apologise for what I wrote, I didn't know all the facts. I hadn't actually heard some people were killed. I removed it from my post.

r3nu4l

colm_mcm wrote: »

Highly unlikely that the footbrake would also fail.

thebiglad wrote: »

Tell that to the relatives of the Lexus occupants in US which sparked this recall.

If Toyota did not think there was something to it then they would not spend immense amounts on a recall, not to mention the bad publicity.

Indeed...read the article

BBC article wrote:

recording of an emergency call from a family of four who died driving a Lexus in California paints a horrifying picture.

The caller says: "We're in a Lexus… and we're going north on 125 and our accelerator is stuck… we're in trouble… there's no brakes… we're approaching the intersection… hold on… hold on and pray… pray."

zilog_jones

thebiglad wrote: »

I thought turning the engine off (even if not as far as steering lock position) would diable the power steering?

Don't forget your hydraulically assisted brakes and (maybe) clutch. And if you turn off the ignition your brake lights will go off, and your dipped or full beams depending on car. Terrible advice to switch off the engine while moving, IMO.

seamus

I got a stuck accelerator on a motorbike once (same as peasant - the cable snapped and jammed in the sleeve). Exact same rules applied, I hit the clutch, hit the brakes and took it out of gear. Then switched off the engine once I'd stopped.

zilog_jones

colm_mcm wrote: »

if it's auto put it into neutral.

Can you actually put a modern auto box into neutral while moving at speed?

colm_mcm

You can on most. usually the only restriction is on reverse and park.

Certainly on Toyotas you can.

KamiKazi

recording of an emergency call from a family of four who died driving a Lexus in California paints a horrifying picture.

The caller says: "We're in a Lexus… and we're going north on 125 and our accelerator is stuck… we're in trouble… there's no brakes… we're approaching the intersection… hold on… hold on and pray… pray."

I'm sorry, but anyone that doesn't know what to do in this situation and instead calls 911 for help should not be in control of a vehicle IMHO.

peasant

KamiKazi wrote: »

I'm sorry, but anyone that doesn't know what to do in this situation and instead calls 911 for help should not be in control of a vehicle IMHO.

That's easy to say from behind your keyboard.
In a theoretical excercise it's all very simple and logical ...unfortunately logic goes out the window when you're approching a dangerous scenario and your car doesn't behave as it should.

In the case of the Lexus family, not engaging neutral and half heartedly pressing the brakes instead would quickly have the brakes fade and become useless ...and then where are you?

Even in my case, where I did press the clutch and did all the right things ...the engine screaming away at you at full tilt seriously affects your concentration and the ability for logical thought.

As I said ...not that easy in real life

KamiKazi

peasant wrote: »

That's easy to say from behind your keyboard.
In a theoretical excercise it's all very simple and logical ...unfortunately logic goes out the window when you're approching a dangerous scenario and your car doesn't behave as it should.

In the case of the Lexus family, not engaging neutral and half heartedly pressing the brakes instead would quickly have the brakes fade and become useless ...and then where are you?

Even in my case, where I did press the clutch and did all the right things ...the engine screaming away at you at full tilt seriously affects your concentration and the ability for logical thought.

As I said ...not that easy in real life

I've had it happen before, it's not pleasant but it's certainly not unrecoverable. You said yourself you managed to negotiate an off ramp and a roundabout before finding a suitable stopping point, I just don't see how the driver of the Lexus saw his only option to be calling 911 for assistance.

JHMEG

peasant wrote: »

more importantly, it also leaves you without brake servo ...which means you will have to push the brakes REALLY hard (pulling out the steering wheel hard) in order to stop. Not a lot of people would be used to doing this.

The booster will have 1 or more likely 2 full braking assists left before it runs out of wheeze.

peasant

KamiKazi wrote: »

I just don't see how the driver of the Lexus saw his only option to be calling 911 for assistance.

A lifetime of driving automatics (and automatics only) could probably introduce enough of a mental block to not be thinking about engaging neutral as a possible solution ...especially while panicking

enda1

The official advice...

Each circumstance may vary, and drivers must use their best judgment, but Toyota is providing the following instructions:


* For vehicles with manual transmission, depress the clutch pedal and shift to Neutral and use the brakes to make a controlled stop at the side of the road and turn off the engine.

* For vehicles with automatic transmission, Multi Mode Transmission or CVT: Shift the transmission gear select lever to the Neutral (N) position and use the brakes to make a controlled stop at the side of the road and turn off the engine.

* If you need to stop immediately, the vehicle can be controlled by stepping firmly and steadily on the brake pedal. Do NOT pump the brake pedal as it will deplete the vacuum utilized for the power brake assist.

* If unable to put the vehicle in Neutral, turn the engine OFF. This will not cause loss of steering or braking control, but the power assist to these systems will be lost.

o If the vehicle is equipped with an Engine Start/Stop button, firmly and steadily push the button for at least three seconds to turn off the engine. Do NOT tap the Engine Start/Stop button.

o If the vehicle is equipped with a conventional key-ignition, turn the ignition key to the ACC position to turn off the engine. Do NOT remove the key from the ignition as this will lock the steering wheel. In the event that a driver experiences an accelerator pedal that sticks in a partial open throttle position or returns slowly to idle position, the vehicle can be controlled with firm and steady application of the brakes. The brakes should not be pumped repeatedly because it could deplete vacuum assist, requiring stronger brake pedal pressure. The vehicle should be driven to the nearest safe location, the engine shut off and a Toyota dealer contacted for assistance.

KamiKazi

peasant wrote: »

A lifetime of driving automatics (and automatics only) could probably introduce enough of a mental block to not be thinking about engaging neutral as a possible solution ...especially while panicking

That argument is fair enough, I do think that learners should have to learn and pass their test in a manual car first. If it had been the case here maybe the outcome would have been different.

Hagar

6. If all else fails, hit something cheap.

Drake66

zilog_jones wrote: »

Don't forget your hydraulically assisted brakes and (maybe) clutch. And if you turn off the ignition your brake lights will go off, and your dipped or full beams depending on car. Terrible advice to switch off the engine while moving, IMO.

My brake lights work just fine when my engine is turned off.

JimmyCrackCorn

Drake66 wrote: »

My brake lights work just fine when my engine is turned off.

what he said

colm_mcm

some cars brake lights don't work with the engine off though. European ones mostly I think.

JimmyCrackCorn

colm_mcm wrote: »

some cars brake lights don't work with the engine off though. European ones mostly I think.

In a life or death situation fook break lights the engine is going to be turned off and if there happens to be anything else i can take advantage of to save mine and other peoples lives ill use that two

zilog_jones

JimmyCrackCorn wrote: »

In a life or death situation fook break lights the engine is going to be turned off and if there happens to be anything else i can take advantage of to save mine and other peoples lives ill use that two

The life:death ratio will be a lot less in in your favour if people driving behind you at high speed do not realize you are braking.
Have you ever tried to brake hard with the engine off? As peasant and I already said they are servo-assisted, which you will lose with no engine.

galwaytt

....mmm...many moons ago, 1990 in fact, I travelled to the UK to bike my new (to me) 'bike: a lovely BMW K100RS. It was, at the time, Hot Poop And resplendant in M-Sport colours.......

actually, here's a pic - ignore the hair :rolleyes: -


Anyhoo, I collected in Reading, went back to Bristol to collect my stuff, and then aimed it for Harwich, for a trip to Holland, to visit my brother.

Anyhoo, somewhere on the A12, barrelling on my new litre-bike, and catching a car in the outside lane, I rolled off throttle. Well, I did...........but the bike most assuredly did not ! :eek:

That was a wobbly one, I'll give you that, but a quick re-grab to accelerate, and then roll it off, and all was well. I had to find a Services to get over it. :eek:

Cause? Throttle cable liable to stiction when hot, and there was iirc, a static issue as well........it involved a new cable, that had an earth wire bonded to it, which was connected to the frame. Bike was then 6 years old, and BeeEmm did it under warranty, as it was a known issue. +1 to them on that, in fairness.

And for no particular reason, last Dec, in a Car Park for the local Christmas Toy Run, what did I see........?

Yep......still going strong.......(84 G 1385)......still running perfectly.......crumbs: am I that old ?




So, it's not just Toyota, and not just 4 wheels.......

GreeBo

I *think* Id switch to N and starting mashing both pedals on and off as hard as I could hoping to dislodge the accelerator.
I dont think Id do anything with the ignition as Im not sure what it would help, bar stopping the engine from screaming?

That said, turning off the engine while in gear should slow the car down right?
Wheel energy wil be used to turn over the engine?

JimmyCrackCorn

zilog_jones wrote: »

The life:death ratio will be a lot less in in your favour if people driving behind you at high speed do not realize you are braking.
Have you ever tried to brake hard with the engine off? As peasant and I already said they are servo-assisted, which you will lose with no engine.

You dont need a servo to break its not fun but it works

Hagar

Not 100% sure but isn't there a risk of engaging the steering lock if the ignition key is turned all the way? Or will that only happen if the key is removed?

colm_mcm

generally the key has to be removed. you will hear a click as you pull the key out.

seanybiker

Make sure your seatbelt is on properly and whip up the hand break, go flying into the ditch and have fun.

JimmyCrackCorn

Hagar wrote: »

Not 100% sure but isn't there a risk of engaging the steering lock if the ignition key is turned all the way? Or will that only happen if the key is removed?

Yes dont do that lock is the last click

KamiKazi

GreeBo wrote: »

That said, turning off the engine while in gear should slow the car down right?
Wheel energy wil be used to turn over the engine?

Unlikely depending on what gear you're in and what speed you're doing. Very likely that you'll have your traction wheels lock up so good luck with that one

Mr Benevolent

This issue is much more difficult to deal with in an automatic imo. I wouldn't rely on the 'box to shift into neutral at speed (although some newer Jags have an interesting quirk of shifting into reverse at high speed) With a manual the clutch would be a lifesaver. In an auto I'd try for neutral, stand on the brake and hope for the best. Another last ditch way of doing it in a manual would be to shift into first. Expensive though, it'd destroy the engine and gearbox in a few seconds.

zilog_jones

Dunno about other cars but I can't shift mine into first unless it's going about <5 MPH - don't some boxes have no syncromesh on first, or is this not the case with anything remotely modern? (I know they often don't for reverse) Maybe there's just no syncromesh left on mine after 12 years

InTheTrees

r3nu4l wrote: »

what if you have a push-button electronic handbrake?

That would be a Fingerbrake.

:eek:

Matt Simis

colm_mcm wrote: »

You can on most. usually the only restriction is on reverse and park.
Certainly on Toyotas you can.

I was reading up on the Lexus incident on some US Forums. The drive did but the car in Neutral but the gearbox either didnt register the move or overrode the signal to prevent box damage.

Also, there have been more accidents than just the Lexus one that sparked this off. There is documentated cases back as far as 2006 that Toyota have been aware of but unwilling to act on (as they were isolated, the old if "X is less than Y, do nothing" formula).

KamiKazi wrote: »

I'm sorry, but anyone that doesn't know what to do in this situation and instead calls 911 for help should not be in control of a vehicle IMHO.

Dont be a tool. He was in the car with 3 adults and his 13 year old daughter (IRC). His brother in law made the call while the drive fought to avoid crashing multiple times.

They tried all brakes, putting car in Neutral, alternating from drive to Neutral (this worked in other cases) etc. From just coming back from driving in the US its worth nothing they dont seem to have much, if anything, seperating the carriageways, here on a motorway I would (failing all else) slide the car into the guard rail to get it to slow down via friction, over there that would flip you into the other carriageway.

peasant

Matt Simis wrote: »

the gearbox either didnt register the move or overrode the signal to prevent box damage.

too many bloody electronics in modern cars

Mr Benevolent

Matt Simis wrote: »

They tried all brakes, putting car in Neutral, alternating from drive to Neutral (this worked in other cases) etc. From just coming back from driving in the US its worth nothing they dont seem to have much, if anything, seperating the carriageways, here on a motorway I would (failing all else) slide the car into the guard rail to get it to slow down via friction, over there that would flip you into the other carriageway.

So the only option would've been to turn off the engine and rely on limited steering and non-servo brakes

Johnny Utah

Dunno, try driving over one of those automatic bollard yokes!

Zubeneschamali

Matt Simis wrote: »

I was reading up on the Lexus incident on some US Forums. The drive did but the car in Neutral but the gearbox either didnt register the move or overrode the signal to prevent box damage

I'd take it with a grain or two of salt. Look up the giant fuss there was about "unintended accelleration" in Audis in the US. Audi took a huge sales hit, there was a massive investigation and...

it concluded that drivers were stamping on the accellerator instead of the brake.

It would be some coincidence if the floor mat in that Lexus jammed the accellerator at the same moment that the car decided to refuse to go into neutral.

Zubeneschamali

Confab wrote: »

So the only option would've been to turn off the engine and rely on limited steering and non-servo brakes

Well, he could have asked the passenger to hold the wheel while he pulled the mats off the pedals.

zilog_jones

This current incident has nothing to do with mats :rolleyes:

Mr Benevolent

Zubeneschamali wrote: »

I'd take it with a grain or two of salt. Look up the giant fuss there was about "unintended accelleration" in Audis in the US. Audi took a huge sales hit, there was a massive investigation and...

it concluded that drivers were stamping on the accellerator instead of the brake.

It would be some coincidence if the floor mat in that Lexus jammed the accellerator at the same moment that the car decided to refuse to go into neutral.

Fair point, drivers resort to old habits and end up killing themselves. Very unlikely that the brake and accelerator would give up at the same time.

Here's a question - which will win, the accelerator or brake pedal? The brakes provides a 0.7-0.9G max decel rate and the accelerator provides a @0.4G accel rate. However at high speed the situation is much different. The ultimate factor is how much braking the pads can provide before the onset of brake fade. That's a question of thermodynamics which I can't answer.

The problem here is training. Drivers are not pilots. They don't know the cars' capabilities and most people will never deliberately reach their cars' limits in their lifetime unless it's in an emergency situation. A classic example is ABS. In an emergency stop most drivers will not press the brakes hard enough to activate the ABS.

Actually I've just had a thought. The ABS might have been the problem here. Imagine you're in the situation that the Lexus driver faced. Stomp on the brakes to the point of ABS activation. Think about it. The ABS computer locks the wheels for a few milliseconds, then unlocks them, allowing the engine to power the wheels again. So now you have a cycle where the car is alternatively powering and braking. Would that provide effective braking? Maybe not.