Jerky Throttle

[impala77]

Hi all, I recently upgraded my 2 door C1 to a 61 plate Yaris SR, (needed more space and 4 doors)

My problem is I can't get on with this car!!! No matter how I try, the gear changes are jerky, when manoeuvring in 1st it's as if the throttle is going on off on off, it kangaroos. And if I need to pull out quickly sometimes it dies or it's jerky like I'm a learner again.

I took the car back to toyota and a mechanic drove it and said because of new laws about esp and emissions, most cars now have electronic throttles and are "jerky". They did reset the ecu to see if it made a difference, (it hasn't yet, but it's only been a few days) I'm so dissapointed as I love the car in all other respects, I just can't drive it smoothly.

My question is, is this really how they all drive? If I'd known it was a fly by wire throttle I don't know if I'd have bought it as I had a C2 by Loeb a few years ago with a dodgy throttle and had to get rid.

I don't want to be paying for a car for 3 years that I don't get on with.

Any help or advice please.

[FROSTYBALLS]

I think with tightening emission regulations, drive by wire throttles will become the norm - if this isn't already the case.My current Auris, the previous two Toyotas and our current Hyundai i20, all have drive by wire throttles - neither my partner nor myself have any issue with how either of these cars drive or drove.

[impala77]

I think all new cars now have drive by wire because it's law to have esp on new cars and esp needs to be able to take control of the throttle. It just feels like it's not registering how much pressure is being applied to the pedal.

[FROSTYBALLS]

ESP became compulsory for all cars with new type approval from November 2011, and became compulsory on all new cars from 31st October 2014. Some manufacturers fitted ESP as standard before October 2014.

For example my 2012 Auris doesn't have ESP (type approval for both the first generation and the current generation Auris dates back to 2007).

However our 2012 Hyundai i20 does - and has had ESP since just after it's introduction in 2009.

[Cyker]

I don't think it is a problem with drive-by-wire throttles specifically, but suspect there is something wrong with the one in yours. Maybe some sort of idle sensor or the actual pedal position sensor is a bit glitchy.

My Yaris D4D is drive by wire but the accelerator is still responsive and accurate, and it is ten years old!

[Catlover]

Joanne, your car may be covered by Toyota 5 year warranty (if certain criteria are met ie servicing). From reading other threads/posts on here it seems SOME dealersare not as quick as coming forward and doing repairs under the warranty scheme as other are or as you would want them.

As others have said the problem you have should not be happening just because its fly by wire technology, ridiculous to expect that in this day and age, irrespective of what your dealer mechanic has said.

You going to have to go back and mither them - it sounds like she who shouts loudest gets the job sorted. Not how it should be but that is how it seems to work.

[impala77]

Thanks guys. I keep telling hubby there's something wrong and he says it's me!! Oh and yes it does have remainder of warranty.

[MikeSh]

There are an awful lot of things that could be wrong. The accelerator pedal is only one input to the Engine Control Unit and all can have an effect. (Incidentally, custom 'tunes' can change the throttle response on drive-by-wire systems, so there is no reason for them to be jerky per se.) Bear in mind that the previous owner might have got rid of the car because it had started to get difficult, so it may be a newish problem with it.

It might be worth getting other things checked, such as a dirty airflow sensor? sticky throttle? (the butterfly in the intake is driven by a motor) even an iffy lambda sensor in the exhaust might be upsetting the mixture.

Of course finding a garage/mechanic who can handle all that might be a problem; even some Toyota dealers may struggle.

[impala77]

Thanks Mike. The toyota guy said he ran diagnostics and it showed no faults and throttle sensors were showing 0 to full throttle, so as you say probably not throttle related as such. This morning on way to work it drove ok then on way home it drove like a bag of spanners again, so it's intermittent. Toyota dealer has been great to be fair, said to give it another 4 weeks and if there's no improvement they'll swap the car, but I don't want to swap the car I just want it fixed!! Would it be worth taking it to another garage/dealer for a second opinion I wonder.

[MikeSh]

This morning on way to work it drove ok then on way home it drove like a bag of spanners again, so it's intermittent. Toyota dealer has been great to be fair, said to give it another 4 weeks and if there's no improvement they'll swap the car, but I don't want to swap the car I just want it fixed!! Would it be worth taking it to another garage/dealer for a second opinion I wonder.

Oh heck. Intermittent is a nightmare, cos Murphy's Law says it won't do it anytime a mechanic is watching.

TBH the give it four weeks sounds more like "Maybe she'll just get used to it" than "Maybe it'll fix itself", because the latter is not a realistic belief.

It might be worth getting another opinion, but you'd need to find someone reasonably familiar and experienced with these systems, so picking an average garage probably won't do. A specialist car tuner might be better able to help as they need to understand all the bits that feed the ECU in order to reprogram them, but that could get expensive.

[impala77]

Yeah pricey! But somethings got to be done, I don't believe for a minute that this is how toyota make cars and send them out of the factory! Think I'm jinxed, every time I get a new (or new to me) car it's got issues grrrrr.

[impala77]

Toyota rang today to see how I'm going on, told them I'm still not happy. Said they'll replace it with any car they've got of equivalent value but they can't do same deal so it'll cost me more a month. I've asked if I can drive an equivalent car to see if it's the same, don't know what else I can ask them to do.

[FROSTYBALLS]

Why not ask them to get a Toyota engineer to look at it - or contact Toyota Customer Services to ask the same question.

[impala77]

Somebody drove it when I took it back last week, said yes it's a bit jerky but that's what they are all like, he reset the ecu saying it will learn my driving style so may improve, it hasn't as yet.

[impala77]

Update. Cars going back today, they've said they'll swap it for anything on forecourt so fingers crossed I can find something I'll get on with!!

[Cyker]

Swap it for either a diesel or a HSD Yaris!!! :D

[impala77]

Test drove a 63 plate yaris to compare, that drove lovely but too expensive, found a 12 plate as a possible swap, drove that and it drove horrible just like mine! It's in the hands of Toyota HQ now as dealer advised contacting toyota directly. I've had a reply already and they are "looking into it" so fingers crossed we'll get something sorted.