Kangoo, 2006 – doesn’t start anymore

Hi there, I hope that the ignorant will help me a little bit further. Back from shopping, I wanted to start the car again: key plugged in and turned a little on the steering wheel to unlock the steering wheel lock. Strangely, this only happened with considerable effort, I was afraid to break out the key in the plastic shell. Then the car jumped on and I started. Still on the parking lot at the front right in the engine room a noise noticed bar. Since my wife and I had a bad time, I drove on with this sound without stopping about three kilometers. I arrived at the kindergarten, I exhibited the engine and took a look into the engine room. But there was obviously nothing to see, which pointed out a defect. Only then the car did not start. Interior lighting, radio, light – everything so far in order. The starter does not make a sound of itself, there is only such a quiet “surr With the help of two neighbors the car was pushed on and started – we could at least drive home. During this trip there were no “side noises” to hear and everything went well. Now the car is standing here at our door, I have zero plan, what it could be – and hope for your help. For this already before a “thank you”. Should details be missing, I will gladly deliver them with a hint of course.