Mmt Problem?

[Raggyroller]

Hiya everyone,

This is my first post here for quite a while...

I bought a 2006 Aygo Black with MMT just the other day.

This is my second Aygo... I had a basic 3-door one for nearly four years, and never regretted buying it for one second... brill!

I parted with it for a campervan.... big mistake!!

A few more cars (and spinal and hip problems) later... trying to find the right one to suit my back comfort, and the fact that I have great difficulty(inc. pain!)in using a clutch.... I tracked down a lovely Aygo Black with clutchless gearchange... MMT!

Most of the time this system is pretty good(not as responsive as the old manual, but still), BUT... whenever the car has been left for more than a few minutes, starting off is VERY strange!!!

If I just let it creep in 'Easy'('Drive'), it sets off with a series of grunts and jerks, and then is off a bit fast for comfort if in a confined space!!!

HELP!!!! Is this an accepted feature of the MMT system, or have I got a problem??

Any help/explanation/sympathy will be much appreciated!

Cheers...

Andrew.

[miss_d_bus]

I wonder if it is doing some kind of kangerooo jumping at around 10-20 mph ish? Mine does that ocassionally when the car is trying to keep it in 2nd gear but it isn't fast enough for 2nd but 1st isn't really appropriate. The speeding up might be it trying to keep in 2nd to stop it stalling.

It is a funny car to drive and its not like a normal automatic so there are quite a few characteristics to get used to!

I've experienced the same sorts of things with an MMT Yaris and an MMT Auris but the Aygo definitely, in my opinion, works better with that gearbox.

Are you able to test drive another Aygo MMT so you could compare the difference?

Other people might have more specific advice...!

[Unklian]

Most of the time this system is pretty good(not as responsive as the old manual, but still), BUT... whenever the car has been left for more than a few minutes, starting off is VERY strange!!!

If I just let it creep in 'Easy'('Drive'), it sets off with a series of grunts and jerks, and then is off a bit fast for comfort if in a confined space!!!

HELP!!!! Is this an accepted feature of the MMT system, or have I got a problem??

Different from "conventional" automatic gearboxes,

the MMT is pretty much a manual gearbox controlled by computer.

What it can't do, is predict hills or sudden changes in circumstances

that a driver can. It has to react to stuff as quickly as it can.

Conventional, fluid coupled automatics were happy to drift along in very slow

traffic with no jerkiness due to their construction.

The MMT, being a manual gearbox at heart has problems with doing that.

If you were to veeeeery gently feed the clutch in on a manual

Aygo and try to filter along in traffic with no throttle, it would get jerky.

eg, if you are on a slight uphill section, the engine may be at the point where

it may stall. The engine management briefly opens the throttle and because you are in gear,

the Aygo jerks forward. Then, the gearbox decides opening the clutch would be a good idea

and things become worse......

It's software is no doubt biased towards......"Get the clutch fully engaged asap to prevent wear"

I slip into neutral a lot when in queueing traffic.

Pop into gear, make a decision to move forwards with slight throttle,

stop, then move again etc.

One thing to remember is that the MMT has exactly the same clutch as a manual so

while you are slipping the clutch in traffic, it is becoming VERY hot.

Not good for any clutch. It will then expand a bit and the Aygo's brain has something else to contend with.

I love my MMT for being incredibly clever but it's still not as good

as a human brain so we have to help it out a bit sometimes!

Any manual car driven with the clutch fully engaged when at tickover rpm becomes very jerky

as soon as you try to open the throttle slightly.

Ian.

[ihpj]

Previous poster pretty much covers the MMT. You have to drive the car as a manual and it is very smooth, relaxing and easy to drive. The creep is an issue as you don't control the bite on the clutch, its down to the car. But other than that, love the MMT.

You will have to learn to change/adapt your driving style TBH to live with the MMT. But the most important thing is to stop treating/viewing/expecting the MMT to behave like a traditional Auto - it isn't that.

[Raggyroller]

Thank you all very much for all your input on this... very much appreciated.

Just to clarify further.... the problem only ever happens when the car is cold. Once I've driven just a very short distance, it behaves properly at take-off in bottom gear... even if I just let it creep.

It's just that very first moving off from the parking space when the engine is cold, when the grunty jerky forward leaping happens.

It was just that I couldn't understand why this should happen when the car has been sitting overnight, but not after it has been driven a few yards. Very strange...

Cheers...

Andrew.

[Unklian]

Thank you all very much for all your input on this... very much appreciated.

Just to clarify further.... the problem only ever happens when the car is cold. Once I've driven just a very short distance, it behaves properly at take-off in bottom gear... even if I just let it creep.

It's just that very first moving off from the parking space when the engine is cold, when the grunty jerky forward leaping happens.

It was just that I couldn't understand why this should happen when the car has been sitting overnight, but not after it has been driven a few yards. Very strange...

Cheers...

Andrew.

You could always try the old "disconnect the Battery for an hour" trick.

Apparently (I'm sure somebody will confirm / deny this) Doing this resets

various things in the Aygo's memory.

I believe it re-learns the clutch.

Don't know if this is a myth but you can try for nothing and see if anything changes.

Anybody ??

Ian.

EDIT: My Aygo is also aggressive on some mornings.

Perhaps condensation / damp on the flywheel making it a bit more grippy.

Perhaps because the idle speed is up a bit on the "choke"

EDIT 2: Just had a thought......I leave my Aygo overnight in reverse with the

handbrake off. It's on the level so I don't like to use the handbrake.

I know that the clutch is left "engaged" when I turn off the engine as the

car will not roll. I don't know weather if you leave your Aygo in Neutral,

weather the clutch is engaged or not. The only reason I mention this is that

if the clutch is "open", condensation on the flywheel is much more likely.

[ihpj]

I use the handbrake - well because thats what it is there for; however if the incline is steep, then yes gear + handbrake. But otherwise, car in neutral and handbrake applied.

Many people who drive Autos get into the 'bad habit' of leaving car in 'P' only. Then are surprised come MOT time why the car fails on handbrake :P

[boukehj]

I have a Corolla Verso MMT and it too is a bit jerky when cold.

It tries to keep idle revs relatively high when cold (1500/min), which makes it more difficult for the clutch to be smooth.

You could always disconnect the Battery to see whether it works. Failure codes in the computer will be lost, but there is probably nothing in there anyhow. It will get the car to relearn, but this means more jerkiness in the first couple of drives.

[Raggyroller]

Thanks again for all the contributions.... much appreciated.

I'll try some of the suggestions and get back to you.

Cheers...

Andrew.

[Dinky_05]

no idea why my post isn't showing....wrote loads.

take it in and get toyota to upgrade the software. made a massive difference to our car - holds first longer and less juddering.

[Raggyroller]

no idea why my post isn't showing....wrote loads.

take it in and get toyota to upgrade the software. made a massive difference to our car - holds first longer and less juddering.

Cheers Dinks... I'll try that one, coz the juddering's a bit dodgy in a tight corner on a cold morning!!

Rags.

[SteveWicks]

I've had the same problems with my 2007 Yaris.

Starting off from cold it jerks into reverse then jerks into first and revs really high struggling to get into second. A couple of mins later all seems ok.

I've just taken it to the dealer and they said the clutch actuator components need replacing.

Maybe this is the problem.

[kav]

I love my MMT for being incredibly clever but it's still not as good

as a human brain so we have to help it out a bit sometimes!

Ian.

me too!