My 98 XK8 has had what sounds like an upper engine noise only when it is first started and run at idle for a few minutes. When driven for just a few minutes (or if you touch the throttle a little), engine is normal and noise is gone. No codes, no other engine performance problems. Car has 154K miles. Any thoughts as to what might be causing this noise and how to resolve the issue? I have attached a link of a youtube video that I posted to explain the noise. Thanks for any tips! - C.J.
1998 Jaguar XK8 Engine Running - YouTube

 

The noise might be the Variable Valve Timing units [VVT]... One way to prove it is to open your bonnet and start the engine WITHOUT TOUCHING THE THROTTLE... Listen for the noise and let the engine settle down from the initial high idle. Once you are certain the noise is present, goose the throttle quickly ONCE,,, about half way down... Doing that forces the VVT's to be exercised and charged with oil...

If the noise shuts up right then, they are the source of the sound. If that's it, that means taking the front of the engine down again to replace them.

Let us Know

 

Wow! That sounded like more than VVT ticking. Did this start suddenly or gradually increase?

Easy, cheap test: add a can of 'Restore', an oil thickener, and let us know what happens. If that helps at the next oil change raise the viscosity of your oil.

 

Test Point,

I thought it sounded like valve clearance or could be VVT but definitely top end. Good news is it goes away with oil pressure so it's not likely to be imminently terminal.

 

I bought the car a few months ago in non-running condition. Once I got it running, the noise was present, and does not get any worse, it is a very consistent noise at first start-up, and will go away with a little throttle rev. The noise does not come back until it has at least sat one day. I have had the car for a few months, but prior to my ownership it had been sitting for awhile, I suspect maybe 1+ year. I have finally got it to the point that it will start and run smoothly. It needed plenty of TLC including key programming and battery replacement. After many replacement parts, almost all hoses, belts, tune-up parts, control arm bushings, it is in much better shape than when I got it. I had changed oil with 5W-30 Castrol according to the factory specs with no improvement to the noise. But, with 154K miles, a thicker oil or restore might be in order. Thanks for all of the suggestions.

 

Identical issues with my 1998, did you ever resolve this and if so, what was done?

Doug

 

My 97 noise is similar but maybe not as loud-- key difference being once warmed
up oil pressure is 5 psi at idle and sensor indicates low oil pressure.