Engine/Clutch shudder upon start-up/creeping

[WazWii]

Hi guys,

Been on this forum a while and replies have been spot on before so thought it worthwhile to give you something to think over. I will try to keep it as simple as I can. 

Basically when starting my AYGO second-generation with MMT gearbox when I release the brake and the car creeps forward on its own momentum (as it is a automatic/manual robotized automatic) there is a shudder and vibration. Quite bad at times. Interestingly this goes away after only 1-2 minutes of driving (sometimes even less). Issue is worser when car has been stood for a while (3 + days). Issue has been present for two years. Not present when car bought new. Issue is worse in reverse gear. More vibration and juddering.

I still cannot figure out if this is engine related or clutch. However one very interesting thing I discovered is that when the car creeps forward the RPM of the engine drops dramatically. Two LED bars drop for those who know the AYGO instrument cluster/dashboard. That to me seems to be stating the car is trying to stall. And yet when the engine has driven for those 1-2 minutes those drops do not occur...

I wonder what this is then. Is the ECU malfunctioning or is the start-up procedure compromised. Maybe there is not the correct mixture of air/fuel upon start-up so maybe the sensors are off. I keep being told it is clutch related and I know there are threads that say similar. However I am unsure as I do not seem to have the classic signs of a clutch wearing out. The issue resolves itself for the most part, as indicated earlier, by just getting the car running/warmed up within 1-2 minutes. However in reverse issue is still present (although a lot better) after getting the car warmed up. Something is telling me (my gut) that it is rev (RPM) related. The revs are too low and no doubt this could be the case in reverse gear. When I let the reverse gear go to its maximum speed (let the car run back as fast as can be) then again the vibration and shudder goes away. 

Any help would be appreciated. 

[Dave the aygo]

I have had the same problem on two of my aygos only does it from cold lasts about a once or twice when pulling away I had one of them looked at by the dealership and they said they cannot find anything wrong?? 

[WazWii]

9 hours ago, Dave the aygo said:

I have had the same problem on two of my aygos only does it from cold lasts about a once or twice when pulling away I had one of them looked at by the dealership and they said they cannot find anything wrong?? 

Same here; dealer said the same to me. Official Toyota licensed. Said it may be a clutch issue and is nothing that is above normal, so basically a quirk of the car. 

However the RPM's clearly drop. The engine clearly gets quiter when creeping. So only at creep does this happen. Creep is related to the MMT robotized manual box I agree and not the manual traditional stick-shift.

Interestingly the clutch cable has been adjusted 2-3 times at prior services and things change for the better by a vast amount only for the issue to re-appear about a month later. The clutch cable adjustment also adjusts the speed of the reverse gear to a much more safer slower amount. But then again about one month later things go back to the distorted original.

Very bizarre. 

[WazWii]

Thought I would bump this;

Anyone?

[DerekHa]

On 6/28/2023 at 3:37 PM, WazWii said:

Same here; dealer said the same to me. Official Toyota licensed. Said it may be a clutch issue and is nothing that is above normal, so basically a quirk of the car. 

However the RPM's clearly drop. The engine clearly gets quiter when creeping. So only at creep does this happen. Creep is related to the MMT robotized manual box I agree and not the manual traditional stick-shift.

Interestingly the clutch cable has been adjusted 2-3 times at prior services and things change for the better by a vast amount only for the issue to re-appear about a month later. The clutch cable adjustment also adjusts the speed of the reverse gear to a much more safer slower amount. But then again about one month later things go back to the distorted original.

Very bizarre. 

Hi there,

I can't speak for the 2017 MMT Aygo but my partner has a 2006 1Lt manual C1 with around 48k miles on the clock bought just over 12 months ago now. Good overall condition, very low miles and has been fairly well looked after. The car always used to shudder quite a lot when pulling away and more so when reversing.

After watching the engine as it ticked over noticed the engine seemed to move a bit too much on the engine mounts. After changing different mounts eventually found that the lower transmission one was the culprit having changed the original one for a decent brand name (went for a Febi one) It's commonly referred to as the dog bone, when you see one you'll see why it gets that name. The rubber bushing perishes over time and usage and lets the engine move and vibrate more than designed too. Could this be your problem?

It's a fairly easy DIY fix to replace these if your able with the spanners, Just two large bolts and a bit of jiggling and it'll come out, but check it's worn/perished first.

One other thing we've found with the C1 is it's not too fond of running on E10 Unleaded.  Much smoother if feed E5 Super Unleaded. I know they "should" run ok on E10 but lots of people seem to find these 3 cylinder engines run happier on E5 petrol, bit of a difference in price but it's somewhat offset by the better MPG. Have also found my little 2013 Skoda Citigo, another 3 cyclinder engine by VW is also lots happier running on E5.

Let us know how you get on please.

[Wiz201]

I had a couple of mk2 Aygos that did feel a bit jerkier in first and second to begin with. I just put it down to the type of engine and the gearbox quirkiness. 

Obviously changing to the CVT on the Aygo X I now don't have those issues.

[Cyker]

For all the criticisms of a CVT, it is buttery smooth!

[WazWii]

On 7/4/2023 at 10:30 PM, DerekHa said:

Hi there,

I can't speak for the 2017 MMT Aygo but my partner has a 2006 1Lt manual C1 with around 48k miles on the clock bought just over 12 months ago now. Good overall condition, very low miles and has been fairly well looked after. The car always used to shudder quite a lot when pulling away and more so when reversing.

After watching the engine as it ticked over noticed the engine seemed to move a bit too much on the engine mounts. After changing different mounts eventually found that the lower transmission one was the culprit having changed the original one for a decent brand name (went for a Febi one) It's commonly referred to as the dog bone, when you see one you'll see why it gets that name. The rubber bushing perishes over time and usage and lets the engine move and vibrate more than designed too. Could this be your problem?

It's a fairly easy DIY fix to replace these if your able with the spanners, Just two large bolts and a bit of jiggling and it'll come out, but check it's worn/perished first.

One other thing we've found with the C1 is it's not too fond of running on E10 Unleaded.  Much smoother if feed E5 Super Unleaded. I know they "should" run ok on E10 but lots of people seem to find these 3 cylinder engines run happier on E5 petrol, bit of a difference in price but it's somewhat offset by the better MPG. Have also found my little 2013 Skoda Citigo, another 3 cyclinder engine by VW is also lots happier running on E5.

Let us know how you get on please.

Do I have to get under the car to see this transmission mount?

Yes I have changed to E5 fuel. Look at my post history. There is a detailed thread where I go into this. You will like what I reported.

Interestingly, just to state again, the shudder gets better after a few minutes of driving. This would indicate that the mount may not be the issue as it would be continous right? Don't get me wrong the shudder is still there but on start-up it is particularly noticeble. I think it is a rev issue upon start-up as it is perhaps tricking the clutch to not get the correct biting point hence the shuddering.  

[DerekHa]

3 minutes ago, WazWii said:

Do I have to get under the car to see this transmission mount?

Yes I have changed to E5 fuel. Look at my post history. There is a detailed thread where I go into this. You will like what I reported.

Interestingly, just to state again, the shudder gets better after a few minutes of driving. This would indicate that the mount may not be the issue as it would be continous right? Don't get me wrong the shudder is still there but on start-up it is particularly noticeble. I think it is a rev issue upon start-up as it is perhaps tricking the clutch to not get the correct biting point hence the shuddering.  

Hi mate,

The mount, dogbone, is almost dead centre under the car so yes you'll need to get it jacked up safely. It holds the bottom of the gearbox casing to the back of the front subframe. Two large bolts hold it in place one horizontal and other vertical. It was fairly straight forward replacing mine, though as stated that was on a 2006 manual.

A link to a used  one on eBay below:-

You can get a new Febi one for  a little more than they seem to be asking for a used one which is what I decided to go with. These bottom mounts are there to stop the natural twisting motion the engine produces and damp the movement. If you can push and pull on the top of the engine (backwards and forwards) and it moves to any appreciable amount then it's likely the dogbone.

I started with the drivers side engiine mount and went back to the original one as the others I bought weren't as good as the old one. The new dogbone made the difference for me.

There's also another mounting on the passenger side of the vehicle under the Battery tray and holds the the top of the gearbox to the engine bay I but don't think they take the flexing like the dogbone does.

[WazWii]

Quote

Hi mate,

The mount, dogbone, is almost dead centre...

Thanks for that reply DerekHa. It was very detailed. I will get my local Toyota dealership to look at this. Car is serviced there and warrantied there you see. 

[DerekHa]

OK WazWii,

Hope you get it all sorted what ever turns out to be. 👍

[WazWii]

On 7/10/2023 at 6:21 PM, DerekHa said:

OK WazWii,

Hope you get it all sorted what ever turns out to be. 👍

Hi again,

This was looked at by the dealers (official Toyota) and they could not see anything of concern. 

[Corollanutter]

My daughter has the exact same issue with her MMT transmision 2018 Suzuki Ignis. Judders for the first couple of start-offs and then it goes away. It is covered at some legth on the Suzuki forums, however there doesn't seem to be a long term (or even medium term) fix for this. Suzukis (and Toyotas) long term fix is to migrate to a CVT gearbox! 

[WazWii]

Interesting. Thanks for that.

This is why I am hesitant to have a full clutch change. Because the issue would just come back again and it seems it is just part of the engineering design from the outset if you get me. 

I have heard it is moisture (condensation) on the clutch when stood. I noticed when you leave it stood for a while it is worse. Also noticed when garaged it is less pronounced. 

[mrfixer]

In all honesty this may be a quirk you have to live with.  All of these 'robotised' manual gearboxes seem to suffer shortcomings - whether its Toyota MMT, Fiat Dualogic, GM Easyshift, Honda ishift etc etc.   Many years ago I did some work on the development of an automated manual transmission with AP transmissions in Leamington Spa.  We had a BMW 5-series fitted with a prototype system.  The physics of power transmission through a single dry plate clutch are fiendishly complicated and it is extremely difficult to control the clutch actuator with sufficient precision to give a smooth take up under all conditions.  Issues like friction material wear, temperature, contamination come into play.

Personally I would avoid any robotised manual gearbox.  CVTs have their shortcomings too but Toyota/Aisin units seem pretty good these days and would be my preference on a small car.