Automatic car issue

GolfBravo

Most people confuse automated transmissions with automatic transmissions.

There are two types of automated transmissions available: CVT (continuous variable transmission) and semi-automatic.

Normal hydraulic automatic transmissions use torque converter instead of clutch to manage the connection between the engine and transmission. CVT usually uses a belt to offer an infinite range of ratios. A semi-auto is just a normal manual transmission with a few extra sensors and actuators to engage clutch and change gears - and yes most European car manufacturers sell them as automatics, but this is just a marketing blurb.

CVT and semi-auto transmissions are only popular in Europe as they offer better MPG than traditional auto transmissions, are more compact and lighter, cheaper, don't require oil radiators, and also suit small capacity engines with low torque. Car manufacturers love selling semi-autos - for an incremental cost of less than £200 they can charge you over £1000 for the privilege of driving an "auto".

So going back to the OP: your car is a semi-auto and yes it will roll back like a manual car, unless it's equipped with a hill holder.

sebastianj

I must say it has been very educational. Mine is an MMT and I have never driven such a car before therefore the confusion. I looked for a dip-stick for the gear box, it does not have one as ukmike and Golfbravo have indicated.
It re-assures me that the car is good, many thanks.
sebastian

LincolnshireYokel

VfM4meplse wrote: »

There's me thinking that automatics were invented for people unable to master the art of gear changes and clutch control .

Americans, then ?

andrew-the-cat

I have a CVT auto and it will roll back on the slightest of hills. I have also driven Honda Civic with CVT gearbox and it behaves the same way.

Our work vans however have a conventional automatic gearbox and also hill hold control, so they will never roll back (or forwards when in reverse) on a hill if you're stationary and take your foot off the brake.

TrickyWicky

Check the car isn't in snow mode if it has one - that will cause it to roll.

Mine doesn't roll but on very steep hills it can - a mild touch of the accelerator keeps it in place.

movilogo

All Toyota MMTs are susceptible to jerk during low speed gear changes and they do roll back on hills. Traditional torque converted autos should not roll back in slight inclines although they will also rollback if the hill is steep and engine is just idling.

Automated manuals are bad things. Either stick with traditional automatics or drive a manual

oldagetraveller

sebastianj wrote: »

I must say it has been very educational. Mine is an MMT and I have never driven such a car before therefore the confusion. I looked for a dip-stick for the gear box, it does not have one as ukmike and Golfbravo have indicated.
It re-assures me that the car is good, many thanks.
sebastian

The "brain" that operates the gearchanges on the MMT is quite thick, by that I mean a bit of a dunce!:p It will change gear at the most inappropriate moments and sometimes, especially when starting off say entering a roundabout, will not change from 1st to 2nd!:cool:
You have to help it out quite a lot in E mode. e.g. it can't see an approaching hill climb coming up, only changes down when it realises - oh, we're going up a hill now. Then part way up the hill, thinks ah, it's good to change up now and does so with the resulting labouring engine and loss of momentum!
Gear changes are made smoother by lifting the throttle off slightly and it will then change.
Does yours have the "flappy paddles" Sebastion? They do make things much easier.
I'm sure your car is behaving as the Toyota MMT should. i.e. non too well.
They've sensibly ditched it for the Mk3 Yaris. Probably too many disgruntled owners, like myself.:)

knightstyle

We have a Toyota Auris MMT, 07 plate so probably the same as the ops.
It does roll back a foot or so on a hill but then something kicks in and it remains stationary.
If it is jerky at low speed try to be gentler on the accelerator, it will still pull away fast enough, you save fuel and no jerking.
We have an auto as my wife has trapped nerves and her left leg doesn't work properly. Used to laugh at autos but now we are on our third I find them much more relaxing to drive.