One of the things that drives many motorists mad is when they get an infuriating knock from the suspension while driving. Many will put up with a whistle or a squeak, but when it’s a knock, they are straight in for me to try and find its source.

The owner of this 2010 Opel Astra 1600 had heard a knocking from the front of his vehicle and was going to come along for a quick diagnosis. On the way to the garage the knocking suddenly stopped and he decided to turn around and see how things went.

The noise never returned and so he drove around quite happily until the NCT. It was then noted that the knocking had been a worn ball joint on the antiroll bar link arm. This has now popped off and so the knocking had stopped.

This had obviously occurred on the way to the garage at the point the knocking had been silenced. The link arms are a very common problem and 80% of the front end knocking problems I see are from a worn antiroll bar link arm. A pair of new link arms was fitted and the motor was good to go.

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