Engine surge in Yaris hybrid automatic

[Miriam Becker]

A few days ago I was sitting in my car on our drive with the engine idling, handbrake on, in reverse, with driver door open, waiting for the front windscreen to defrost.

Without warning the engine roared loudly and the car reversed at high speed across the road and through the fence of the garden opposite our house, narrowly missing a pedestrian

Has anyone has a similar incident?

[flash22]

Why did you have it in gear ?? if you are not in the car it shouldn't be in gear as you are not in control - tbh its user error

[shaunchipchase]

possibly  car switching from electric back to petrol power....hence the surge......take it out of gear when idling

[Dan_Q]

Best thread ever. Subscribed

[HughA]

Something wrong here.  In reverse the car will only move using the electric motor. The petrol engine cannot drive the wheels in reverse, it can only charge the Battery. Without a foot on the accelerator and with the hand brake on I can't see how the car can reverse at high speed; it might creep a bit though! I agree that the car should be in park whenever the driver is not in control!  If it did reverse at high speed there is a fault and should be investigated by a Toyota dealer.

[flash22]

In reverse, it will only engage the motor when the throttle is pressed, the handbrake should hold the car under light throttle, the only point the engine would be running in reverse is if the Battery was charging (as said above) interesting

Edit. The handbrake could have failed or been knocked

[Catlover]

Is this a wind up? I just can’t believe someone would be sat in a car, in reverse, engine running, WAITING, for the windscreen to defrost. 

[flash22]

20 minutes ago, Catlover said:

Is this a wind up? I just can’t believe someone would be sat in a car, in reverse, engine running, WAITING, for the windscreen to defrost. 

Nope its got a plug - well the new Prius does

[Miriam Becker]

This is not a wind up and I was sitting in the car waiting for the engine to warm up and allow warm air to defrost the windscreen when, without any warning, the car shot backwards. 
I am particularly interested to hear if this has happened to anyone else.

[Catlover]

But why was you not just sat in the car waiting for windscreen to clear but IN REVERSE. Why?

[HughA]

Is it possible that when the car started to move back you went for the brake but hit the accelerator?  It's not unheard of for this to happen in an automatic when you weren't expecting it to move.