I have used this forum over and over, invaluable tool.. I have changed tensioners, Chain, Gaskets, Heater Hoses, Water Pump, Thermostat, Knock sensors both banks, I still get lean bank #1 code, but My real concern is that when I start the motor, it runs smooth and responds great, after a 10 min drive or just sitting, the motor starts to sound like its knocking and ticking.. I am wondering if my timing is out and or why and what would make it go out, Might not be timing at all. I would appreciate any help on this.

1999 xk8 4.0

Seriously starting to look at a ls1 conversion, but would hate to do it. I love the 4.0 when it runs right.

 

xk8florida,

I've moved your post from the Jaguar Forums Advice / Feedback & Suggestion Centre section to the XK8/XKR section.

You'll get the answers here.

Graham

 

Remove your accessory belt and see if it still ticks.

 

Good day!!

When was the last time you changed your oil and what weight and type did you use?! There has been much debate over the weight of oil... Lower number means more can flow from the pump keeping fresh oil where it needs to be.......... OR... Get the higher number oil to keep it thicker at the higher temps to keep the metal bit in the motor from touching under extreme pressures....... Yada yada yada... I prefer it thicker - old school maybe... It does sound like it is thinning out too much... Experiment... 0W-20 full synth... If it stays the same go to 10W-30... Oh, and to take detenation out of the scenario, use the expensive gas for two tanks... Higher octane for higher compression motors...

Good luck and let us know...

Thanks and Cheers!!!

 

I like the 'remove the accessory belt' test!

A quick and cheap test of oil weight issues is to add a can of an oil thickener such as 'Restore'. For $5 you can tell if moving to a higher weight oil is going to solve the problem. Won't hurt.

I didn't see any mention of mileage.

 

The reason I recommended removing the belt is that I have a ticking noise that I couldn't seem to isolate, so someone suggested the idler pulley. I changed the pulley to a plastic one from metal (both used parts FYI) and the noise changed- this tells me that is my issue. (the belt slides on the pulley and snaps back repeatedly and the slack on the bearings allows a "ticking" noise.

I also have a slightly deformed harmonic balancer, so when I get that repaired I will change out all my pulleys as well for a nice silent motor.

 

A video (audio actually) would be most helpful. Like you (on a different car) I once had an issue of noise once warmed up...It was a bad main bearing that was quiet when cold, but ounce warmed up, would make a knock at idle in park/neutral. Put in gear, no noise because there was just enough load. Anyhow, impossible to tell without hearing it.