Engine Mechanical problem
2002 Other Nissan Models 4 cyl Four Wheel Drive Automatic 58,000 miles
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I'm in Kingston, Jamaica and seek your help.

My 2002 Nissan X-Trail has an intermittent rattling noise heard 2-3 seconds on cold start-ups before the sound disappears. It does not recur if the car is immediately restarted. Initially, the upper timing chain tensioner was suspected to be at faulty.

In February 2008, both upper and lower timing chain tensioners, upper and lower timing chains, chain guides and oil pump were replaced by the dealer to correct a timing problem which developed after my mechanic replaced the head gasket and resurfaced the cylinder head in October 2007.

On hearing the noise, I took the car back to the dealer for a recheck. They replaced the upper tensioner and even replaced the oil with new 10W30 oil but the problem remains.

The mechanic at the dealer who worked on the vehicle eventually heard the sound when he started it the second morning during the recheck, and was baffled as no contaminants were found in the oil screen or channels under the valve cover. He suspects the intermittent noise is caused by low oil pressure due to an improperly fitted head gasket. He claims the the oil pressure relief is not the problem, despite my doubts and says the noise won't cause and engine damage.

I've already spent US$1600 and am very frustrated at not having had this problem resolved. Please help.

Philip