Blue smoke on extended idle. 2006 4.8is.

[craigatkinson]

I have a 2006 BMW X5 4.8is. I have been having the blue smoke on extended idle issue. I am pretty sure it is the valve stem seals, but wanted to make sure that I have correctly diagnosed the issue before taking the plunge.

I usually see the smoke when I am in stop and go traffic, or going through a drive thru. When I am finally able to give the vehicle a lot of throttle, it spits out a big plume of smoke. I do not notice smoking while driving down the road. I do not have smoke when I first start the vehicle in the morning, or any time it's been just sitting turned off.

I tried to get the smoke to start yesterday in my garage, but it wouldn't smoke unless I got in the car and moved it around a little big in a stop and go fashion. But once I got it smoking it smoked real well.

The lack of smoke when the car starts makes me wonder if it really is the valve stem seals. I have always been under the impression that bad valve stem seals would cause a plume of smoke upon start up, but then once the car warmed up would stop smoking.

I already changed the PCV valves and it didn't change anything, and there was nothing wrong with the valves I replaced. Any help would be appreciated. I read in another forum of someone having the same problem and replaced a bunch of seals and gaskets under the valve covers, didn't replace the valve stem seals, and it fixed his problem.

I'd like to avoid pulling the cams if I can.