Could a worn tensioner pulley be the cause of knocking and vibration in a BMW?

BMW driver question

For some time now, I have been hearing soft knocks at slow speeds and feeling a slight vibration. After slightly adding gas, the problem stops. I should add that the engine dies and fires evenly, so the pulley should be fine. Could a worn tensioner pulley be the cause of the malfunction?

The problem occurred on a BMW 318i E90 129KM with 175,000 km, but it can happen on other models as well.

BMW 320d E90 | By Thomas doerfer (Own work)[CC BY 3.0], via Wikimedia Commons

Response from BM Cars service

The described problem can be related to very many components, related to the rotating engine. If knocking noises can be heard and vibrations can be felt, the cause could be either excessive wear on the pulley or the dual mass pulley. A worn tensioner pulley can give a rubbing or rumbling noise, but metallic rattling, should not be heard.

For an accurate diagnosis, a full diagnostic of the vehicle is necessary.

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BMW 3 E90 | By nakhon100 (BMW 320si E90)[CC BY 2.0], via Wikimedia Commons