About half the time when I start my 2000 XK8 up, I get a large (and brief) cloud of blue oil smoke (car has 59,000 miles). The rest of the time I get nothing. My original prognosis was intake valve seals, but I tried letting it back down in a lower gear and then hit the gas - no smoke. I'm wondering if the crankcase ventilation system is somehow pressurizing the crankcase (intermittently) and forcing oil past the rings. I get some pretty nasty looks when the cloud initially appears, but it's done a lot to reduce the local mosquito population.

Anyone have this problem, or an idea what it might be?

 

Intake seal wear causes a puff of smoke on startup. Ring wear results in a puff after backing down and hitting the gas.

 

Valve guide seals. If you are using 5w 30w oil move up to 10w 30w and see what takes place. I had this issue on my 93 xjs and it worked.

 

Check the part load breather orifice. If plugged or restricted it may be sucking oil through the full load breather tube.

 

Here is the link if needed.
http://www.jagrepair.com/images/TSB/...20Breather.pdf

 

Great! I'll give this a try. Thanks again; this forum has made owning this car so much more enjoyable (and saved me lots of $$$).