Hello, I have a Corsa 2004 1.0 and a strange failure appeared six months ago. When reaching the operating temperature, a noise starts to be heard, as if it were a tappet. When cold, however, the engine is barely heard. I took my vehicle to the agency, where I was told it was the distribution that was causing my problem, and that I needed to replace it together with the tensor. But my doubt is: if my car has got a timing belt, wasn't it that it does not need to be replaced? Or am I wrong? I hope you can help me, and thanks beforehand.

I just put new pistils and new valves tested by engineer now the engine backfires when we start the nd in a process it backfires... plugs new timing belt set...now what could be problem help?