Car Seems To Accelerate By Itself

[grahamsmythe]

Yes, this sounds like exactly the same problem.

I don't drive the car too much, as it's my wife's and she's been complaining about this for a couple of weeks now.

We both went out in the car last night and I noticed that the pedal doesn't return back to where it should be, thus increasing the speed and revs.

As far as I know, there isn't a cable between the pedal on our car and the carburettor, as it's electronically controlled, so I think I can rule out a sticky cable.

There is NOTHING that's getting stuck behind the pedal as we don't have mats in our car.

What day are you taking your car to the garage?

[miss_d_bus]

Yes, this sounds like exactly the same problem.

I don't drive the car too much, as it's my wife's and she's been complaining about this for a couple of weeks now.

We both went out in the car last night and I noticed that the pedal doesn't return back to where it should be, thus increasing the speed and revs.

As far as I know, there isn't a cable between the pedal on our car and the carburettor, as it's electronically controlled, so I think I can rule out a sticky cable.

There is NOTHING that's getting stuck behind the pedal as we don't have mats in our car.

What day are you taking your car to the garage?

It is as if you are describing my car !

I'm taking mine in on Wednesday and will have one of their company cars for two days and will return it late Thursday.

From what I understand, there is some sort of sensor in there and a butterfly thing. I am far from technical (as you may well guess) but it would suggest to me that the issue is localised to that part of the car rather than my first thought that it was to do with the clutch and/or gearbox. There is no engine warning light so my thought is that it doesn't relate to anythng hi-tech but its all guesswork on my part.

I don't hold out much hope with this problem unless the technicans see the fault for themselves. At the moment its just my say so. Grr!

I'll keep you posted onthe progress with it but I will make sure that they know that I am not the only one with this problem so they don't fob me off as a silly blonde girl!

[grahamsmythe]

Yes, this sounds like exactly the same problem.

I don't drive the car too much, as it's my wife's and she's been complaining about this for a couple of weeks now.

We both went out in the car last night and I noticed that the pedal doesn't return back to where it should be, thus increasing the speed and revs.

As far as I know, there isn't a cable between the pedal on our car and the carburettor, as it's electronically controlled, so I think I can rule out a sticky cable.

There is NOTHING that's getting stuck behind the pedal as we don't have mats in our car.

What day are you taking your car to the garage?

It is as if you are describing my car !

I'm taking mine in on Wednesday and will have one of their company cars for two days and will return it late Thursday.

From what I understand, there is some sort of sensor in there and a butterfly thing. I am far from technical (as you may well guess) but it would suggest to me that the issue is localised to that part of the car rather than my first thought that it was to do with the clutch and/or gearbox. There is no engine warning light so my thought is that it doesn't relate to anythng hi-tech but its all guesswork on my part.

I don't hold out much hope with this problem unless the technicans see the fault for themselves. At the moment its just my say so. Grr!

I'll keep you posted onthe progress with it but I will make sure that they know that I am not the only one with this problem so they don't fob me off as a silly blonde girl!

Is your car manual or semi-automatic?

Mine is the semi-automatic variety with a tiptronic gearbox.

I might have a look at our car tonight at the pedal sensor to see if I can see anything.

I'll report back if I find anything. Let me know what the garage says to you.

Regards

Graham

[Unklian]

I'm just wondering if it's something really simple.

Perhaps just the shaft on which the throttle pedal

lives needs lubricating.

If you press the throttle with your hand then V..e..r..y slowly release it, does

it return to the same level as when you allow it to "spring" back from fully depressed?

Might be a simple lube job?

Hopefully.

Ian.

[miss_d_bus]

I'm just wondering if it's something really simple.

Perhaps just the shaft on which the throttle pedal

lives needs lubricating.

If you press the throttle with your hand then V..e..r..y slowly release it, does

it return to the same level as when you allow it to "spring" back from fully depressed?

Might be a simple lube job?

Hopefully.

Ian.

I really hope it is that simple! Next time its not getting dark, I'll have a look and see if that happens. It would be another thing to tell Toyota.

The car I have is the MMT.

[roses100]

Hi, I seem to have been experiencing the exact same problems myself in my MMT 07 Aygo.

Sometimes there has been slight delays in responsiveness when you take your foot off the accelerator, so for example I'll be going uphill at 40mph, and I take my foot off the gas, the Aygo will still stick at 40mph without slowing down briefly. Its been happening for a while and I thought it was all in my head.

Then this week it randomly wanted to shoot up the hill at 10mph when I was sitting in a traffic jam and it happened a couple of times. I usually stick it in E to stop it rolling backwards and have no problems on this road . So when this happened I stuck the Aygo into neutral, it started to revving really high like a boy racer... making me look like a bit of a lemon frankly when I'm in traffic with nowhere to go ;)

So I took it into my Toyota dealer, at first nothing came up in the computers, but when they double checked my throttle pedal, they found that it needed replacing, and apparently the throttle pedal has some sort of computer chip aswell. Hoping this info might help, especially for miss_d_bus

[zakelwe]

Interesting that they are all MMT ! Good luck guys and gals.

I have an MMT but my throttle pedal is always pushed to the carpet, so I might not have noticed if it had stuck B)

Andy

[roses100]

Interesting that they are all MMT ! Good luck guys and gals.

I have an MMT but my throttle pedal is always pushed to the carpet, so I might not have noticed if it had stuck B)

Andy

Yeah must be all those darn computer chips causing havoc ;) but it's strange how its happening to MMT Aygos particularly

Hehehe I'm the same, although to be fair it's only got a 1.0 engine lol

[Jan van de Wouw]

Interesting that they are all MMT !

If your car is equipped with ESP/VSC (or whatever Toyota decided to

call it) you've also got the Throttle-By-Wire system like the M-MT has.

Now that others arer starting to notice this too I'm also leaning towards

suspecting the Accelerator-pedal sensor or return-spring (or both).

[Lancastrian]

Hi everybody,

This evening I put " throttle jamming on Aygo " into Google and got to this thread and have just registered. Fascinating thread in the light of my experience.

Many months ago I spoke to my local Toyota garage regarding a problem I had with the Aygo Plus about 4 years old bought from new ( Semi Automatic with MMT)

Intermittently the car would keep going at the same speed even though I took my foot of the accelerator and on start up would also over rev and take me forward without me putting my foot on the accelerator & I had to apply the foot brake to hold it back. They said they weren't familiar with the problem I outlined and as it wasn't doing it when I made the call asked me to bring it in if the fault reappeared.

The car ran alright in the main for many months apart from some brief recurrences of the problem which didn't last long enough for me to take it to the garage in the "fault " position .

On Monday of this week I got into the the car on the drive late afternoon to pick my grandaughter up from college and got quite a fright.

I put the car into neutral ,started up .engaged forward drive and without me touching the accelerator the car launched forward at very high revs and I had to slam on the brakes as it was hurtling towards a flower bed.

There was a smell of burning rubber from the tyres as I struggled to hold the car back.

I switched off tried again and even in neutral the car went into a high state of revs.

I didn't even try to engage forward drive.

So I abandoned the Aygo on the drive and took my wife's car.

I tried again later & the same happened again.

It seemed to jam into a high rev state even in neutral. The engine was screaming at a high rate of revs

I telephoned the garage again and they tried to fob me off with a story about car revs being higher when the engine is cold.

I said it wasn't just higher revs it was revs which were screaming and out of control and it was dangerous. I was then advised to make sure the Toyota floor mat was not jammed under the pedal - I had already checked that but to make absolutely sure I took the mat out of the car.

I switchted on again in neutral andt the engine still screamed in high revs.

I phoned the garage and said it was vey dangerous and undriveable - They suggested that I call in the AA which I did and the AA man said that in his opinion the accelarator pedal was jamming and he freed it off somehow and got it driveable again.

I then arranged to drive it to the garage yesterday morning , explained what the AA man had said and said that I also thought the throttle was jamming somehow (I had a case of the throttle cable jamming me on a Triumph Dolomite in the 1970's - similar experience but not as bad ) and left it with them.

I rang later today and they said they had tried it from cold in the morning and again from cold in the afternoon and could find nothing wrong and would try it again in the morning.

They said that unless trhe fault replicated whilst they had it in their poseession they "couldn't attach it to their computer to diagnose what was wrong." I appreciate that intermittent faults must be difficult to trace.

I have been driving since 1959 and apart from the Dolomite (minor experience ) I have never experienced anything like this.

It will be interesting to see what " fob " story the garage try to palm me off with tomorrow.

My knowledge of car mechanics is somewhat limited particularly in respect to modern technology and I am rather at the mercy of the Toyota dealership where I have been a customer for well over 10 years.

[grahamsmythe]

I'm a bit of a DIY mechanic and have just taken the whole throttle assembly out.

It doesn't look as though there are any serviceable parts there, as it looks like a sealed unit.

I've just given the 'moving' part a good spray of WD40.

As our car is just out of warranty, if Toyota don't issue a recall, and if my spray of WD40 doesn't solve the problem, I imagine that it can be fixed by just buying a new accelerator assembly (the whole thing being electronic).

It looks expensive - anyone know how much they cost?!

[zakelwe]

Hi everybody,

This evening I put " throttle jamming on Aygo " into Google and got to this thread and have just registered. Fascinating thread in the light of my experience.

Many months ago I spoke to my local Toyota garage regarding a problem I had with the Aygo Plus about 4 years old bought from new ( Semi Automatic with MMT)

Intermittently the car would keep going at the same speed even though I took my foot of the accelerator and on start up would also over rev and take me forward without me putting my foot on the accelerator & I had to apply the foot brake to hold it back. They said they weren't familiar with the problem I outlined and as it wasn't doing it when I made the call asked me to bring it in if the fault reappeared.

The car ran alright in the main for many months apart from some brief recurrences of the problem which didn't last long enough for me to take it to the garage in the "fault " position .

On Monday of this week I got into the the car on the drive late afternoon to pick my grandaughter up from college and got quite a fright.

I put the car into neutral ,started up .engaged forward drive and without me touching the accelerator the car launched forward at very high revs and I had to slam on the brakes as it was hurtling towards a flower bed.

There was a smell of burning rubber from the tyres as I struggled to hold the car back.

I switched off tried again and even in neutral the car went into a high state of revs.

I didn't even try to engage forward drive.

So I abandoned the Aygo on the drive and took my wife's car.

I tried again later & the same happened again.

It seemed to jam into a high rev state even in neutral. The engine was screaming at a high rate of revs

I telephoned the garage again and they tried to fob me off with a story about car revs being higher when the engine is cold.

I said it wasn't just higher revs it was revs which were screaming and out of control and it was dangerous. I was then advised to make sure the Toyota floor mat was not jammed under the pedal - I had already checked that but to make absolutely sure I took the mat out of the car.

I switchted on again in neutral andt the engine still screamed in high revs.

I phoned the garage and said it was vey dangerous and undriveable - They suggested that I call in the AA which I did and the AA man said that in his opinion the accelarator pedal was jamming and he freed it off somehow and got it driveable again.

I then arranged to drive it to the garage yesterday morning , explained what the AA man had said and said that I also thought the throttle was jamming somehow (I had a case of the throttle cable jamming me on a Triumph Dolomite in the 1970's - similar experience but not as bad ) and left it with them.

I rang later today and they said they had tried it from cold in the morning and again from cold in the afternoon and could find nothing wrong and would try it again in the morning.

They said that unless trhe fault replicated whilst they had it in their poseession they "couldn't attach it to their computer to diagnose what was wrong." I appreciate that intermittent faults must be difficult to trace.

I have been driving since 1959 and apart from the Dolomite (minor experience ) I have never experienced anything like this.

It will be interesting to see what " fob " story the garage try to palm me off with tomorrow.

My knowledge of car mechanics is somewhat limited particularly in respect to modern technology and I am rather at the mercy of the Toyota dealership where I have been a customer for well over 10 years.

Hi Lancastrian, welcome to the forum, shame you had to join on account of this dangerous occurance. It's a shame the AA man did not give you more details on what he did to free it, that might have been useful for the garage. Yes, I have squeeky chair runners that don't squeek when it is with the garage so they don't get fixed

Good luck and let us know how you get on.

Andy

[benchan]

I got exactly the same problem here and I got a 55 plate MMT.

My gas pedal stays stuck to the floor, and I can hear "squeaks" from the pedal assembly. If I pump the pedal a few times before I start the engine, it stays less sticky.

Can this be fixed DIY?

Ben

[miss_d_bus]

Fippin' heck!!! I've opened a huge can of worms!!

I can report that my car has been fixed. If the pedal is sticking and you can correct the problem by pulling up the accelerator pedal by putting your foot underneath it then it is mechanical but its not to say that there won't be further electronic symptoms caused by the sticking further down the line. The problem for me was not with the pedal itself but further into the engine somewhere. I am not able to fully explain it as I did not follow entirely when the dealer told me what was wrong but I understand that a plate of some sort was sticking and to sort this involved getting a part that could not be resourced quickly. As far as I am concerned, so far the problem seems to have gone away but since I have only had the car one day, then its still early to see if it comes back.

To summarise these were my findings:

* The car can rev by itself in netural

* The car can accelerate up hills by itself - its been as much as 10 mph

* The car on even and flat road surfaces seems like it has cruise control

* The car can feel out of control and too fast going round corners and roundabouts and going down hills

* Turning the engine on and off does not fix the revving issue where the accelerator pedal has not been touched

* It does it regardless of being E or M mode

* The brake operates normally

* Sometimes the gears selected seem higher than what would usually be expected in E mode

* AND FINALLY the speed/revs problem goes away when you put your foot under the accelerator and pull it up

If your car fits within those things, I would probably go as far as to say there is probably a serious defect with the MMTs with premature failure of a very important component and I am certainly prepared to "do my bit" in making Toyota aware of this if anyone requires support in getting this problem sorted. Put it this way, when the fault was finally recognised, Toyota Canterbury did the right thing and would not give me my car back whilst they were waiting for the part to come in which was for nearly a week. They clearly felt it would be inappropriate for me to drive the car under their corporate responsibility as it was dangerous and obviously I could potentially have ended up dead given that I do a lot of fast road driving.

Although my car is fixed, its starting to show that this problem is not isolated.

I will ring Toyota back in a week or so to tell them if the problem is still there or not - I can ask for how much it would cost for the repair if anyone is interested.

[Lancastrian]

Many thanks for the information.

Glad to hear that your car has been fixed. :)

My Aygo is still with the Toyota Garage.

To be fair, they have since reassured me that they will resolve the problem for me and will only return it when they are happy that everything is OK.( I have bought Toyotas from them for over 10 years now and am willing to accept their word on this)

I last spoke to them 2 days ago and they have promised to update me tomorrow.

[Jamesbelfast]

I have came across similar problems on other makes of cars and not just those with automatic transmissions. On fly-by-wire throttle systems the accelerator pedal works similar to the volume control on a radio whereby as you move the pedal or knob the current either increases or decreases. These are known as Potentiometers (commonly known as Pots). This sends a signal to the ECU which in turn sends a voltage to the motorised throttle body telling it to either open or close. It is well known in electronic circles that a variation in the voltage supply can affect their performance. When the engine speed seems to vary on its own the first thing to check is the voltage output of both the car Battery and the alternator. Also any additional electrical systems added to the car can also have an effect. Also load sensors on the auto-transmission and engine can affect the ECU and if it receives erroneous signals strange things can start to happen. Whilst it may appear to be a manufacturing problem finding the exact cause may be difficult as there are so many aspects to the throttle controls on modern cars. On top of this the software in the ECU can also cause headaches.:)

[roses100]

Wow I'v certainly learnt alot about automatic gearboxes by following this thread! Iv just has my car back today after experiencing the same symptoms as miss_d_bus, and was also told by my local Toyota dealer not to drive it too untill they fixed it. They said they've replaced the whole throttle pedal unit, fingers crossed it's been fixed as the problem did not occur on my way home from work. I just hope that the definate cause of this problem is found soon, as its a rather dangerous defect, if it's the case. My throttle pedal has always been squeaky for the last year or so, but it's only towards the runup of that acceleration problem did is squeak more loudly and often lol

[Loftylad]

Oh 'eck! :o

http://news.yahoo.com/s/afp/20091125/ts_al..._20091125125005

Only in the US though... ???

[miss_d_bus]

Oh 'eck! :o

http://news.yahoo.com/s/afp/20091125/ts_al..._20091125125005

Only in the US though... ???

That applies I believe to models that are not sold in the UK and the blaming on the mats is not the whole story. I think they are the big SUV cars with the full automatic gearboxes. I have read that there have been issues where they are unable to put the car into neutral in order to stop it when the accelerator pedal gets stuck and the brake stops working.

This is definitely not an issue in the Aygo :) I am 100% sure that brakes do not stop working when the accelerator pedal sticks on and if the brake did fail, well thats seriously bad luck for both faults to occur at the same time. Anyway, lifting up the accelerator pedal is the 'fix', at least in my car.

Incidentally, a different garage to where I got my car fixed rang me up to get me interested in buying a new Aygo Blue MMT with a trade-in for my Aygo +. I mentioned there was no way I would buy another Aygo MMT when there seems to be people with problems with their accelerator pedal sticking and faults developing betweeb 2-4 years into the vehicle's life - he reckoned it was news to him about the issue. I'd be interested to know if the 2009 Aygo model has basically the same parts for its throttle system and therefore still potentially prone to this fault. Hmmmm

[shropshire lass]

Fippin' heck!!! I've opened a huge can of worms!!

I can report that my car has been fixed. If the pedal is sticking and you can correct the problem by pulling up the accelerator pedal by putting your foot underneath it then it is mechanical but its not to say that there won't be further electronic symptoms caused by the sticking further down the line. The problem for me was not with the pedal itself but further into the engine somewhere. I am not able to fully explain it as I did not follow entirely when the dealer told me what was wrong but I understand that a plate of some sort was sticking and to sort this involved getting a part that could not be resourced quickly. As far as I am concerned, so far the problem seems to have gone away but since I have only had the car one day, then its still early to see if it comes back.

To summarise these were my findings:

* The car can rev by itself in netural

* The car can accelerate up hills by itself - its been as much as 10 mph

* The car on even and flat road surfaces seems like it has cruise control

* The car can feel out of control and too fast going round corners and roundabouts and going down hills

* Turning the engine on and off does not fix the revving issue where the accelerator pedal has not been touched

* It does it regardless of being E or M mode

* The brake operates normally

* Sometimes the gears selected seem higher than what would usually be expected in E mode

* AND FINALLY the speed/revs problem goes away when you put your foot under the accelerator and pull it up

If your car fits within those things, I would probably go as far as to say there is probably a serious defect with the MMTs with premature failure of a very important component and I am certainly prepared to "do my bit" in making Toyota aware of this if anyone requires support in getting this problem sorted. Put it this way, when the fault was finally recognised, Toyota Canterbury did the right thing and would not give me my car back whilst they were waiting for the part to come in which was for nearly a week. They clearly felt it would be inappropriate for me to drive the car under their corporate responsibility as it was dangerous and obviously I could potentially have ended up dead given that I do a lot of fast road driving.

Although my car is fixed, its starting to show that this problem is not isolated.

I will ring Toyota back in a week or so to tell them if the problem is still there or not - I can ask for how much it would cost for the repair if anyone is interested.

Hi

How is your car behaving now? I have just bought an 06 Aygo MMT and it doing exactly the thing you describe - very scary! Like you, I thought I was imagining things at first, but yesterday it tried to hurl me into the oncoming trafffic at a junction, I could hardly hold it on the brakes so put it into neutral and the revs went sky high! My car is guaranteed for another month and the seller says he will get it fixed if I can get Toyota to diagnose it and give him a price. I wonder how much Toyota Canterbury charged you and what the part was that it needed? I asked Toyota Shrewsbury about it but of course they said they had never heard of the problem!!

[miss_d_bus]

I guess it is right to assume the problem I had with my car is what is Toyota is now recalling over.

I believe the failed part in my car was actually just replaced with another "dodgy" part so I guess I have the hassle of getting done AGAIN with the new safe part!!!

ARGH!

[grahamsmythe]

Obviously this whole thing is related to the recent recall?!

Ironically enough we haven't had the same problem since I sprayed some WD40 on the accelerator!

[miss_d_bus]

Obviously this whole thing is related to the recent recall?!

Ironically enough we haven't had the same problem since I sprayed some WD40 on the accelerator!

i'd assume it is related. It seems strange if it wasn't.

It may well be hard to prove either way but certainly with my car, I don't think a bit of WD40 would have fixed it as I got the feeling that the failed part was non-serviceable.

Good news that you fixed your issue :)

[laurap]

Post deleted

[laurap]

Post deleted