does Jaguar have any kind of warranty for this, vehicle has only 70,000 miles but rattles when cold.
what steps should be taken now to avoid major trouble in the future? How dangerous is it to keep driving, does not make noise whan engine is warm. thanks, Mike

 

Welcome to the forum Mike. I don't think there have been reports of tensioners or guides failing with your engine. Yet. But there is no recall. You need to remove the valve covers and inspect the chain system, or have a competent independent specialist look at it. I would avoid going to a dealer as they would likely tell you a new engine is called for.

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Wouldn't a 2004 model be an X350 ? Different engine, 4.2, I believe, with a different valve train setup from the X308.