Any advice on why my 1.9TD XuD makes a noisy tapping noise at start up? When engine reaches operating temp the tapping noise quietens down but still audible especially when waiting in traffic queues. Can't hear it at speed on road only when doing a speed upto 40mph ish. On acceleration the noise increases then quietens when at a cruising speed. Tapping noise disappears when decelerating and the engine sounds really healthy. Any ideas? Anything to worry about? I'm off to France in a couple of weeks with my two teenagers so peace of mind would be great. It a recon engine with 40k miles - so they said.