clunk/judder as car accelerates from standstill.

[dm18]

Hi, I am have had my Auris Touring Hybrid for 3 months now, overall very happy so far, but I want to see if this behaviour is normal for the transmission of a hybrid?

On pulling away from a standstill gently the power take up is very smooth, but if I need to prod the accelerator a bit more (e.g. to pull out on a roundabout) there is a discernable judder/clunk - is this normal for these cars?  I took it back to Toyota and they said it's just the engine kicking in - but it seems to do this even if the engine is already running...

Car is a Toyota approved used on a 2018 plate, Full Toyota Dealer history. 34k mileage.

thanks for any advice

 

 

[Saxmaniac]

There's a slight ***** as the engine kicks in, nothing loud or violent, I always go easy on the throttle up to when the engine would kick in just to give the mechanical bits an easier time. If you floor the throttle from standstill, it's not kind to the shock absorbing device between engine and transmission (nor most of the other bits)

[dm18]

thanks for the info,

I'm certainly not talking about flooring it though.  thanks for taking time to respond.

[TonyHSD]

1 hour ago, Saxmaniac said:

There's a slight ***** as the engine kicks in, nothing loud or violent, I always go easy on the throttle up to when the engine would kick in just to give the mechanical bits an easier time. If you floor the throttle from standstill, it's not kind to the shock absorbing device between engine and transmission (nor most of the other bits)

Very good suggestion. I do exactly the same. 👍

[TonyHSD]

40 minutes ago, dm18 said:

thanks for the info,

I'm certainly not talking about flooring it though.  thanks for taking time to respond.

Hi, 

what petrol are you using E10 95 or E5 99? 

If you wait until the tank is almost empty and refill full with E5 99 you may find that the transition from electric to petrol is much smoother with minimal or no thud at all. Also the engine will be quiter and more responsive, the car will feel lighter and more agile and you can get extra 3-5mpg over e10 95 regular petrol. If the car been checked by Toyota garage and nothing unusual been noted then you don’t have anything to worry about. Tesco momentum e5 99 is almost same price as regular petrol from other garages . 👍
Regards 

[dm18]

Hi Tony,

Using E5 for last 4k since I bought the car, still getting a bit of a 'thud', but happy to live with it if its a characteristic of the car.  It seems very rare to have any problems with this drivetrain. 

 

thanks dan.

[Ramos]

Hi, I get the same judder when I accelerate and it stops as soon as I ease off the gas. Don’t think it’s a petrol type thing or the process of switching between the two engines. I still don’t know what is it however it’s getting worse by the time and it’s getting more juddery if i’d say, anyone have any idea on what it could be? 

[Saxmaniac]

What's been described above is just a single very mild jolt as the engine kicks in. If you've got juddering while it runs then you could have one of any number of things from misfire to engine mounts or whatever so it wants diagnosing 

[Gerg]

As well as all the above, has the car had a Catlok (exhaust catalyst anti-theft plate) fitted?

If the plate has been incorrectly fitted, or has been 'reprofiled' by a speed bump, then I would imagine that your symptoms would largely fit this.

If it's a genuine Toyota-supplied Catlok, these seem, anecdotally at least, to be more prone to this deforming by the 'road' than some others,, especially if the car is heavily-loaded. 

This is more problematic for the genuine Toyota one as it's quite substantial and sits slightly further away from the underbody (closer to the ground) than some other protection devices, or so I believe.

When the car is accelerating harder, by whatever engine propulsion, the rubber engine mounts bear that torque reaction (Newtonian laws!), so the engine unit will rotate further than it normally would, pushing the exhaust into a space it would not ordinarily exist in.  Is your Catlock (assuming there is one) occupying some of the exhaust's 'wiggle' room - causing a clunk when they hit each other?

But this isn't just a Toyota-fitted Catlok problem - it can happen with any of them.

Just an idea...

[dm18]

Hi,

ref original behaviour - it only happens at pulling off from standstill, not when car is already moving.

Don't think a cat loc is fitted - will check and update, but doesn't sound like a metal on metal noise of that type - more the kind of thunk noise you'd get if you made a clumsy manual gear change.

 

d

[TonyHSD]

14 minutes ago, dm18 said:

Hi,

ref original behaviour - it only happens at pulling off from standstill, not when car is already moving.

Don't think a cat loc is fitted - will check and update, but doesn't sound like a metal on metal noise of that type - more the kind of thunk noise you'd get if you made a clumsy manual gear change.

 

d

Hi, 

What you describe is exactly the damper clutch springs gets fully loaded , manual transmission if you release clutch faster. Reasons for that can be various. Your car is low mileage and you said you ate using E5 only. Let assume that there is nothing broken with your car the common reason for this event on initial switch between electric and petrol is likely the start of the engine as a result of poor fuel quality or anything along the fuel air delivery to the engine, spark plugs, air filter, egr, fuel injectors. Your car is too new and at low miles to get any of these suspicion. I will suggest again another tip: wait until half tank of fuel and refill at BP with M&S shop E10 95 full tank. Drive the car for a while and see if any changes. You can also add a fuel additive to the tank, no harm can happen. You can buy wynns injector cleaner https://www.ebay.co.uk/itm/155155231125?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=fzglve2usx6&sssrc=2349624&ssuid=p34UK1z2T4m&var=&widget_ver=artemis&media=COPY

pour it in and add bp e10 95 to fill up full. 

Drive as usual but a motorway run of at least 30 min constant drive at 60-65mph is recommended and a few brisk accelerations. The longer drive is to rise temperature and burn any carbon buildup, the brisk acceleration is to blow away these dirt and particulates out of exhaust and any water that might be seated along your exhaust system. 
No need of very high speeds or hard acceleration to the floor, just slightly more spirited drive within the law., fun and helpful 🚗🏁👍

After all that completed you may notice smother engine run and less thuds. 

[dm18]

Hi Tony,

 

Thanks,

The clutch damper springs explanation sounds consistent with the kind of noise/feel I am getting.

I did run a bottle of Toyota's fuel additive through when I bought the car, its had 4 motorway trips of 70mph/420 miles so far since then, didn't affect the thud...  Engine runs sweetly otherwise. 

Perhaps the previous owner did a lot of short trips and coked up fuel system?  I have used Terraclean on previous diesel cars for a proper clean...

 

[TonyHSD]

40 minutes ago, dm18 said:

Hi Tony,

 

Thanks,

The clutch damper springs explanation sounds consistent with the kind of noise/feel I am getting.

I did run a bottle of Toyota's fuel additive through when I bought the car, its had 4 motorway trips of 70mph/420 miles so far since then, didn't affect the thud...  Engine runs sweetly otherwise. 

Perhaps the previous owner did a lot of short trips and coked up fuel system?  I have used Terraclean on previous diesel cars for a proper clean...

 

Hi Dan, 

yes it could be that because of low use previously. You can try the trick with e10 and e5 half half and see if the same. What is your usual driving mode Eco, Normal or Power (sport) ? 
Driving in Normal mode is the best. In other two modes you can have this thud more often because in eco the car is dead literally until you floor it and in power is too sensitive. Any fast switch between electric and petrol will come with thud for sure. 
I drive in Normal mode and start slowly on ev for the first few meters then push the accelerator further and the car switches to petrol very smoothly and with e5 or mixture e5/e10 the car is silky smooth. 👍