Hello all, I posted this in the wrong forum originally so thought I would retry here, sorry about the double posting to any mods. I am fairly new to the Jaguar world but I did a lot of research before I made my purchase ( I bought a 1998 XJ8). The service records show that the timing chains and the tensioners were replaced and when I had some work done recently, my mechanic said he inspected the primary tensioners and they had indeed been replaced with the upgraded models. When I start the car cold it was fine and no issues to speak of, but as it warms at a low idle a slight ticking starts in the engine. If I rev the engine once the ticking keeps pace with the RPMs but if I rev it a second time, the ticking starts to speed up but then you can hear an audible CLICK and the ticking stops til the engine has been at low idle for a while again. I am concerned that one of the secondaries or even one of the primary replacements is going bad and is "popping" to full extension when I rev it enough to get enough hydrolic pressure in it, The ticking never seems to get worse and never occurs at high idle. The car runs flawlessly other than that noise..I am not sure where I should be looking. Thanks for your time

 

If indeed all of the tensioners are the new upgrade metal bodied ones (not just "new" old style ones), I suspect you are just hearing some VVT noise. I have never heard any on my car, but I cannot hear worth a flip anyway, but many folks hear theirs. Restore and engine snake oil additives are reported to help quiet them down.

As you say, about the only thing you should worry about is if it is the tensioners!

 

d

 

+1 on Sparkenzap.

I hear mine ticking from time to time, had the same worries, but concluded it is the right side VVT.
I will go for a slightly thicker oil as maintenance is due.
This should solve it as well.

E.

 

I checked again and yes, all of the tensioners were replaced with the series 3 metal versions. I will look in to the VVT noise. Thanks for the help.