'06 XK8 Cam Tensioner??
 

Engine has a ticking or tapping sound at idle, not real loud, but sounds like a noisy lifter. So is this likely the secondary cam tensioner? I thought that by '06 the tensioners were "upgraded" and not a problem? Car only has 53,500 miles on it.

If not the tensioner, is there something else I need to look into?

Appreciate any insight....have not had to do any engine work at all on this car for the 8 years of ownership other than oil changes.

Thanks.

Three potential sources from a historical perspective:

Accessory tensioner(s) and or accessories such as alternator, PS pump, AC Compressor. Easy to test by removing belt.

VVT units can make a ticking noise at low speed/low oil pressure. Usually goes away above 1500 rpm. Add a can of RESTORE or increase the 'weight' of the oil.

Cam chain tensioners, even the metal ones can fail. The metal tensioners have a ratchet like operation that keeps the chain under tension even without oil pressure. There have been reports of that ratcheting action failing.

Although I have not isolated the ticking noise yet, it was after the car had been driven for 15 miles in 95°F air temp....so it was well warmed-up.

I need to do further investigation to attempt to isolate the noise and will do so shortly.

I also found that the right side upper coolant hose is all soft and not holding shape. New one on order.

FWIW, mine had that issue as well. I ended up replacing it of course, but also took advantage of the cooling system being open to replace the whole plastic assembly this hose connects to. It contains the thermostat, sensor and a bunch of plastic parts with gaskets. These plastic parts apparently become brittle over time, and I did not want to chance it too much longer. At about $100, it seems like money well spent. Make sure you get DEXCOOL coolant to top it off (or better, flush it all out if applicable).

Couple of other things: removing the back bolts require removing the front metal intake plate (obvious when you get there). Some folks get a new gasket for this. Also, the very top of the plastic assembly has a hard plastic pipe going back to the coolant expansion tank. Mine broke on sight (very brittle from age). You might want to change it to a standard coolant hose (about 3 ft.) of small diameter with a couple of clamps.

Best of luck, keep us posted.

If you are opening the cooling system on a car 9 years old there are lots of plastic and rubber things that need replacing. Lots of us have replaced the thermostat housing without removing the intake manifold.

The easiest way to get to the unreachable bolts is to use a pair of pliers to break the plastic housing away until they are fully exposed. You are going to trash the housing anyway. Consider using an aluminum replacement and painting it flat black. The bright aluminum is going to look seriously out of place on an otherwise black engine and will corrode to the finish of all the other unprotected aluminum on the car. Most that have gone through this have replaced the 8mm hex bolts with cap screws so an Allen wrench can get to them.

No aluminum housing for the '06.

Some updates:
Speaking of brittle plastic!!!!...the fan cowl or shroud....I found it broken at the right side mounting bolt so it was moving around a bit....grabbed it to move it back into place against the radiator and a piece broke off in my hand....had previously happened....but this time the entire cowl/shroud just begin to disengrate into chunks and pieces. Was not long and one fan was completely free and hanging by the electrical harness.
Sooooo....time to replace that. Found out that have to purchase the entire assembly including fans at $820.....OUCH!!! It is on order, going to take about 2 weeks to get it to me.

Anyone need a cooling fan or module? Seems that I will have extras.

Also started the engine this morning to attempt to isolate the ticking noise...and of course no ticking noise present. Ran engine for about 5 minutes and no ticking noise. Hunted around with a stethoscope, checking left and right side cams with only "ticking" I could find was the fuel pressure regulator....which is supposed to.

I guess I will just have to wait until I get the new fans installed so I can run the engine longer. Car is sitting until then.

Oh and the right side upper coolant hose was no longer sucked in....think I have a leak at the reservoir. Going to replace the hose between the thermostat housing and reservior with a length of rubber hose.

And agree with RJ237...no aluminun housing for the '06....as I looked and looked and cound not find one.

Thanks for the responses.

The tapping noise could be the "purge valve". Google it and try a search on the forum. My 06 xkr had the same problem particularly in cold (sub zero) temperatures.

If it is the purge valve, the tapping tempo will be independent of the engine revs and can be accompanied by the smell of petrol (although this was not the case for me). The purge valve is located to the rear of the front left wheel arch although I heard it more prominently from the footwell of the coupé.

I delivered my XKR to Jaguar and they said the noise was normal and not anything to worry about. There is a TSB regarding the PV for earlier models where they install an insulated bag to muffle the noise but my car had the new PV with the insulated bag and I assume yours does too.

Good luck.

NorJag: The ticking comes from the engine and is RPM related, so not the PV in my case....but thanks for the response...good information to know about.

I am still awaiting for the fan cowl to arrive, before I can investigate further.