Mmt Hesitation When Cold

[savitar]

Hi all,

I am new to the forum so thanks in advance for any advice.

I just purchased a 07 MMT Aygo Blue (18K miles) and notice that it is VERY rough when first taking off from Cold (starts up just fin). It almost stalls the engine and bunny hops all over the place (reminded me of when I was 17 and learning to drive). :)

After about 3-5 minutes of driving it goes back to being very smooth.

I have searched around the forum but can not find anything about this, does anyone have any thoughts? Clutch? Air Mass sensor?

Thanks,

[daveyjp]

Sounds like a clutch actuator issue. Best advice is to take it back to the dealer, but you may have to leave it overnight so they can try it from a cold start. If you can video the problem it may help when you take it in.

[savitar]

Thanks Daveyjp. I bought it from a dealer specifically because it came with a full warranty so I hope this covers the fix required (if there needs to be one).

It needs to go back to them to finish some paint work anyway so not a bad idea to just leave it in there and get them to look...

[Mickey Monk]

I would say its more likely the MAF (mass air flow sensor) and engine temp sensor. It sounds like the fuel metering is incorrect when running from cold.

[Dinky_05]

i had the same issue. take it back. we had around three resets over the years, just got it back from a dealer who actually knows the car (not lexus only) and just had to have the actuator, ecu and clutch replaced. the car has never been better.

it took a while to get anyone to believe the problem as it doesn't happen when warm.....you also hearing a crack noise as it changes gear and then getting some lurching?

good luck with it.....its expensive if that's what it comes down to. we may have been unlucky (or lucky now it is sorted), but it should not judder, shake, lurch or anything else. hammer it home with them....its expensive otherwise. we kept the toyota warranty which has paid for itself as this is now the second lot of gearbox stuff we have had done.

if it helps, and i have no idea what this means, the gearbox was outof cycle on our ecu (?). the reset and software update may be all you need so don't freakout yet, but if it reoccurs then be all over them.

[savitar]

Hey Dinky_05 - Thanks for the update. I was hoping to find someone who has had this issue. I have been told by Toyota that the warranty I have is basically like have buying a new car, so fingers crossed no matter what it is, they will just fix it.

I will update once I speak wiith toyota later today

[Dinky_05]

keep us posted on how you get on.

the resets did work, but the problem always came back, which is why we stuck with the extended warranty. i can't tell you how much better the car is now, i think it must have always been a problem from new (ours is an '05 and one of the first in the UK with MMT).

it drives so much better.

stick at them with it, and fine, accept a reset as it may sort you out. also the software got updated at some point around 2007 (allegedly) so see if that's been done.

we totally lost confidence in our local lexus guys as our car seemed to be the only mmt aygo they saw. where abouts are you based? i can send on the dealer details of who sorted out ours and they were great with the warranty side, no argument at all.

the ecus alone are apparently about a grand so it is certainly a bill you don't want post-warranty. if we had not had the warranty i would have told them to keep it :)

god i sound scary - it may not be as bad as my experience, so don't panic just yet, but i'm pretty grumpy about it as it took four dealers and five years to get someone who actually identified the problem and fixed it properly.

[savitar]

Hey Dinky_05,

I am based in Cambridge but will be moving to Edinburgh in a few weeks (don't ask... :)

I am not scared by your comments, I actually very much apprecaite them. As I have the full 12 month warranty I am going to insist that they fix it till it goes away and if that means a new ecu / clutch etc then so be it, I will push them for it.

I spoke with the Toyota guy and they still have some paint work to complete which was agreed in the sale so they are going to pick the car up from my house, leave a temp car, and then get the paint work done as well as look into this hesitation issue. Great service actually, very impressed so far. So hopefully it gets fixed with a reset. It is a 07 model so if it does have the upgraded software then it might actually work with the reset.

Thanks again for the advise and if you do happy to know of someone around Cambridge / Edinburgh I would certainly be interested in your views on them.