What's causing the ticking noise from my Aston Martin DB9 engine?

There is a ticking noise from the engine of my 2004 Aston Martin DB9, which I’m told could be the “big-end bearings”. What do you think?

KK, London

We spoke to the Aston experts at Bamford Rose (bamfordrose.com), who gave two likely causes.

If you’re lucky and the noise is a metallic ticking, you need to replace the hydraulic valve lifters, at a cost of about £2,000.

If it is a deeper, knocking sound, the problem is in the bearings on the “big” and “little” ends of the connecting rods linking the pistons to the crankshaft. They can only be reached by removing the engine, so the job will cost, say, £15,000 at an independent garage; a franchised dealer will simply replace the engine for £20,000.

Worn bearings are usually caused by a low oil level. Act now or risk worse damage.

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INSPECTOR GADGET
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