I have a 1998 XJ8. I hear a knocking noise (valve lifter noise) at start-up. If I rev the motor to about 1500 rpm to 2000 rpm or start moving it goes away. It always happens. I mentioned it to the dealer and they said it would be a lot of money to look into.
I have also read a few forums and all I can find is " It sounds to me like the timing chain tensioner(s) are sticking, making the timing chain loose, at higher revs the tensioner becomes unstuck (the clunk sound) and releases, tightening the chain and ending the noise. It is not normal, the tensioners may not have been installed correctly or they may be sticking because they are dirty".
Before I spend the money to look into this I would love to know what might be wrong.
Any assistance would be appreciated
Monday, October 9th, 2006 AT 4:20 PM