Intermittent violent shudder

[Supertaf]

My 2019 2.0 corolla has just developed a very strange and quite frightening problem. Going on holiday last Sunday about 100 miles in on the M5 south of Bristol it felt as if I was running over an incredibly rough surface but only for a second or 2. It then did it again on several occasions during the holiday causing a very slow trip home. Seems to be front orientated, maybe left front and oddly more when going up hill. It also isn't speed dependant so not wheel balance. Causes the whole car to shudder violently. Tyres are fine, no obvious play in the wheel/suspension. Car runs fine and CVT seems fine. Car has done 75000 with a FSH every 10k. Any ideas??

[Hardy888]

I had something kinda similar a few years ago on my 308 diesel and it was a damaged fuel line.

Whatever it is it's one for a mechanic urgently.

[TonyHSD]

Anything like that 

 

[Supertaf]

15 hours ago, TonyHSD said:

Anything like that 

 

Not really. The engine seems sweet, it's also only lasts a second or so. It's a weird one.

[Supertaf]

15 hours ago, Hardy888 said:

I had something kinda similar a few years ago on my 308 diesel and it was a damaged fuel line.

Whatever it is it's one for a mechanic urgently.

It doesn't seem like an engine issue though, I've monitored the rev counter during wobbles and it's constant. It's all through the wheels it seems. Could be CVT I guess but I've no experience of CVT issues to know 

[TonyHSD]

3 hours ago, Supertaf said:

It doesn't seem like an engine issue though, I've monitored the rev counter during wobbles and it's constant. It's all through the wheels it seems. Could be CVT I guess but I've no experience of CVT issues to know 

eCVT it’s only a name to characterise the type of transmission however there is nothing similar to conventional cvt transmission and they does not go wrong. The only thing that can eventually wear out or even break it’s the clutch damper, this usually happens when you have violent engine knocking like the one from the video and you keep driving the car for a long time. If you push the car to the limit every time you start from stand still also can wear the clutch springs prematurely. Differential bearings and gears plus all other bearings may wear out but after many more miles. Cv joints too., all these should have a lot more life in them before eventually cause any issues. What fuel are you using E5 99 or E10 95? You can try to change from one to the other and see if the problem returns. Check suspension, tyres pressure and wear, these can indicate something and point you to some direction. Engine and transmission mounts can also cause similar problems as per your description. 
Regards 👍

[Supertaf]

On 5/8/2022 at 8:00 PM, TonyHSD said:

eCVT it’s only a name to characterise the type of transmission however there is nothing similar to conventional cvt transmission and they does not go wrong. The only thing that can eventually wear out or even break it’s the clutch damper, this usually happens when you have violent engine knocking like the one from the video and you keep driving the car for a long time. If you push the car to the limit every time you start from stand still also can wear the clutch springs prematurely. Differential bearings and gears plus all other bearings may wear out but after many more miles. Cv joints too., all these should have a lot more life in them before eventually cause any issues. What fuel are you using E5 99 or E10 95? You can try to change from one to the other and see if the problem returns. Check suspension, tyres pressure and wear, these can indicate something and point you to some direction. Engine and transmission mounts can also cause similar problems as per your description. 
Regards 👍

Cheers for all that. It's been years since I actually worked with cars and a lot of the new tech goes over my head. I've checked most logical things and it doesn't appear to be an engine issue, the wobble being through the car and steering ( like I'm running over a while line with the rumble bars built in). Going in shortly so hopefully the garage can identify.

[TonyHSD]

3 minutes ago, Supertaf said:

Cheers for all that. It's been years since I actually worked with cars and a lot of the new tech goes over my head. I've checked most logical things and it doesn't appear to be an engine issue, the wobble being through the car and steering ( like I'm running over a while line with the rumble bars built in). Going in shortly so hopefully the garage can identify.

This can be just the tyres and the road surface. Some places the roads are really bad, easily can make the driver think something wrong with the car 👍

[Rambler56]

On 5/10/2022 at 9:52 PM, Supertaf said:

...... the wobble being through the car and steering ( like I'm running over a while line with the rumble bars built in). Going in shortly so hopefully the garage can identify.

There is a stretch (100 metres) of road near where I live that looks normal but feels like you are driving over rumble strips but with all 4 tyres.  It's some sort of special road surface/covering that is designed to warn the driver of accident black spots or close to poor junctions and the noise and vibration it sets off makes most people lift off the accelerator.   Or (tongue in cheek) maybe it's to warn blind drivers of the hazard ahead🙃