Starter does not engage but spring like boinging sound!

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I know the title sounds a little strange but so is the actual noise coming from the starter motor.

It's my mother-in-laws Terios that has the problem. All was well until she was pulled over for a police spot check. When she came to start the car it would not turn over and so she called me to rescue her.

I turned the key and although the starter turns it is not turning the engine over, The noise can only be described as a metal coil spring spinning and hitting stuff as it turns.

I decided to bump start the car to get it back to my place. The engine started no problem but the spring like noise is still there. It does not increase in loudness or get any worst as speed is picked up. The engine runs fine and has full power although the engine management is on orange.

Does anyone have any idea what this could be?
I will be jacking it up tomorrow or weekend but hoped to get an idea what it might be first.

Cheers in advance.