I've had limited experiences when these engines start making lifter noise, but it has always resulted in cylinder head failures. The last being being a dropped intake valve seat. The one before that were the camshaft bearing caps being loose and then the camshaft eventually snapped. The lifter noise in both cases was most noticeable when the temperature gage showed the engine to be warmed up.
However this new instance of lifter noise on my third supercharged V8 is only prominent at idle and low rpm when the engine temp shows cold. The engine always becomes silent when warmed up.
Has anyone had similiar experiences? I'm wondering how long I can keep driving this car before I regret not selling it while it still runs OK.
I know the next thing is to pull the valve covers and measure lifter clearance at both temperatures.
Thank you,
Mike

 

just found all the threads on this subject. The previous owner had a all new primary and secondary tensioners and chain guides replaced. This XJR has no VVT, but maybe one of the new secondary tensioners has a problem...that would be delightful to find as it is an easy fix.

 

You are in the XJ6 forum. Look for the X308 forum. There have been some reports of metal body tensioners not locking in the raised position, but I think that was after thousands of miles. Check also the X350/358 forum for the 4.2 engines which all have them.

Are you in Roch. NY. I lived there many years.

 

Thank you for redirecting me to the X308. Not sure how my req wound up on XJ6. Sounds like you have found a warmer place to spend the winters. Seems like only the seat bottoms of the heated seats warm up on my 1999 XJR. I'll have to check the service manuals and see if the upper portions even have heating elements.
Have a nice evening,
Mike