Yaris T Spirit 1.3 CVT 2012 suspected clutch fault

[Phil Lewis]

Hi all, I wondered if anyone could shed any light on issue with my Wife’s Toyota Yaris T Spirit VVT – I CVT (2012) 1.3cc 110.000 miles, purchased from New.

We have noticed over some time now, from pulling away normally, the engine revs high but doesn’t pull, I can only describe as almost if driving on a frozen lake or sheet of ice, or as if towing a caravan etc. Once it’s on the open road it drives fine, just takes a while to get there. It used to be very nippy!

I’m convinced there is something wrong with the Automatic gearbox or rather the clutch maybe?

This car has the CVT semi-automatic gearbox apparently & can be put into manual mode with tiptronic type gear change + & - paddles on the steering etc. but this feature rarely used.

It’s just had a full service at local garage costing £460 I mentioned this issue to them beforehand and asked them to road test & check this for themselves, they said they had & could not find any fault? I personally think they forgot to do this as when I asked the service reception guy about the outcome he was hesitant and didn’t even know it was an automatic?!

One other strange thing that I have noticed happen only sometimes, when going down a fairly steep hill, not using any accelerator only the brakes or using engine brake, the engine will spontaneously rev really high as if put into neutral with foot on the accelerator, this will continue until levelling out or kicking the accelerator a few times to stop it?   

Anyone else had this same fault before or any suggestions what it could be with this type of CVT transmission?

Thanks in advance

[CPN]

The "local garage" you describe? Was it a Toyota dealer?

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[Devon Aygo]

Both traits you mention are normal functions:

1. Probably the biggest complaint of a CVT transmission where the revs do not seem to match progress, there is no clutch when you press the throttle the revs raise and the transmission selects a ratio this creates what people describe as the "rubber band" effect as the car accelerates up to speed and the revs tail off. perfectly normal.

2. Revs raising when going down hill is in effect the opposite of the above the car can detect downhill sections and lowers the gear ratio, raising engine revs as it gives engine braking stopping the car from accelerating as it otherwise would.

[mrfixer]

I believe your car is fitted with the MultiDrive-S CVT.  Its basically a CVT but with programmed stepped-ratios and the paddle shifters.

This gearbox has a segmented steel push-belt and is driven via a torque convertor. There is no clutch.  Your description sounds a bit like failure of the stator ring inside the torque convertor - like the sprag clutch is not locking and the stator is just spinning.  There are many other possibilities though.

Assuming it has the right amount of fluid then first thing is to get fault codes read. The CVTs are largely non-servicable. Any major failure is best dealt with by fitting a secondhand replacement. 

[mrfixer]

10 minutes ago, Devon Aygo said:

Both traits you mention are normal functions:

1. Probably the biggest complaint of a CVT transmission where the revs do not seem to match progress, there is no clutch when you press the throttle the revs raise and the transmission selects a ratio this creates what people describe as the "rubber band" effect as the car accelerates up to speed and the revs tail off. perfectly normal.

2. Revs raising when going down hill is in effect the opposite of the above the car can detect downhill sections and lowers the gear ratio, raising engine revs as it gives engine braking stopping the car from accelerating as it otherwise would.

Agree with what you say but he's had the car 7 years and 110k miles so presumably used to its normal operation.

[flash22]

Has the CVT fluid ever been changed ? Find an auto gearbox specialist and get it changed 60-100K is about right for CVT

CVt's do generate more heat than a traditional auto box and the nature of the CVT means the fluid wears out - the molecules get pounded and become less efficient just like engine oil does