Hi all,
Owned an XJ6 in the 80s & loved it but had to get rid of it after 6 months or so due to financial obligations. Just purchased a 99 XJ8 & I love it. Clean in and out! It does have an annoying valve chatter when the engine is running hot. Not so much at regular operating temps but extended stop & go driving in 70+ temps! Any ideas would be appreciated.
Dave.

 

Or valve knocking as its also called.

 

Welcome to the forum!

The XJ8 has overhead cams pushing (sorta) on the valve stems so there is usually very little valve noise. A more common noise is the Variable Valve Timing (VVT) unit which can make a clicking noise, usually around 1500 RPM's or less. You don't say what the mileage is but the VVT noise is associated with higher mileage cars and is addressed by using a higher weight oil or an oil additive such as 'Restore'.

Based on your limited comments that is about the best I can do at the moment.

 

Thank you for the welcome & i apologize for not clarifying the issue.
Its a valve pinging sound exactly like the sound when one uses a lower octane gas that they should.

I only hear the pinging at lower rpm as you pointed out, when the engine is hot & under stress as in driving up gradients. Ive already replaced the oil with 20-50 & the pinging has decreased by 50% or so (in frequency) but still there.
Thank you

 

Are you getting any CEL codes that might indicate failing knock sensors?

Otherwise, at under 1500 RPM's I would still vote for VVT's. You are not hurting anything. Throw a can of 'Restore' in with the oil and see what happens.

How many miles?

 

Thank you for the input. No codes. 125K. i will give the restore a shot tomorrow & report back.