Hello!

If my 2007 XK has been sitting more than an hour or two, I get a lot of clatter from the engine for 1-2 seconds at startup. My MGs did this due -- I think -- to lack of oil galleries at the top of the engine or in the head (XPAG engine) so I'm tempted to chalk it up to British "engineering" but I also want to ask around to see if that's normal. Anyone else experience this?

The problem always disappears quickly. I checked and the oil level (5W30 semi synthetic) is full on the dipstick.

Thanks!

 

Never heard any clatter from my 2007 XK. How many miles on your car? Got ~42k on mine.

 

Could be the timing chain tensioners, which may not be providing tension until the oil pressure gets up. Has the car always made the noise, or is it something new?

 

Thought that was a 5.0 issue. Does it apply to the 4.2's as well?

 

There are also the uppers.

On the 4.0L these are routinely replaced with the
version from the 4.2L. Nonetheless, having seen
them up close and personal ... I don't think they
are particularly durable.

On a NA v8 you have to consider whether the VVT
is in good health as well.

 

Thanks everyone. I've only owned the car for the past 7 months/5000 miles but the noisy startup has always been present.

I'm looking for a Jag specialist to take it to or (reluctantly) the dealership (not highly regarded in our area).

 

Sounds like the VVT solenoids are starved of oil on startup giving a loud startup. Quite common on higher mileage V8 4.2 engines.

 

An old trick for older vehicles to clean the gunk out of the oil passages and such was to drain about a quart of oil and add a quart of transmission fluid to the crank case. Run it for about ten miles or so and then change the oil and filter.
The reasoning is that the transmission fluid has cleaning capabilities that the oil does not, so therefore the gunk gets cleaned out. DON'T drive an extended period on the mixed oil, but enough to have it work its magic.
I've never done this on any of my Jaguars, but it really did work on my other vehicles.
So, there ya go...

 

I got my car back from the Jag dealer: long story short, the engine issue was described by the inspecting mechanic who commented "Too expensive to diagnose any further." And then a comment to the effect that if it gets worse, deal with it then. Not overly helpful. I'll continue to look for a Jag specialist in town.