There are tons of DIY in the How To section of the forum.

Yes, the X5 4.6is has the M62TU B46 engine (4.6 liter engine w/single VANOS)...and the link to the video in my reply above would apply to your situation.

And you can also see all the part and how everything is connected by using one of the parts database sites (feel free to save all 3 sites below for future reference): :)

1. RealOEM.com * Online BMW Parts Catalog
2. BMW Parts Catalog
3. Maximillian Importing Company :: Mobile Traditon Licensee

Item #2 in the diagram below is where the diaphragm is located (the round cap with the spring and orange rubber thingy) on the back side of the engine near the firewall. You can buy the whole cover #2...but you may be able to buy the repair kit that BMW sells for the N62...it's the same size...and just reuse the old cover and spring (cleaned up of course)...and insert the new diaphragm).

Again, if you watch the video in the link above...it should help with what to look for and what can be done in a much easier way than trying to remove the whole cover from the backside of the engine. As Edwin mentions, there are no other moving parts in the cover...it just contains the orange diaphram and spring...and the diaphragm is what usually fails by splitting or tearing.

TIP: I've heard that a simple paint can tool works really great for removing the round cap where the orange diaphragm is...the slightly rounded tip fits perfectly beneath the cap and allows you to separate it from either the cover (M62) or the valve cover (N62). :)

great post!!!
 

Very good pics You should get a prize!!!!

I too had been having rough idle- only when very cold- less than ~40 degrees. Emboldened by the thread here, I ordered them before I left last Sat. I returned this morning and replaced them. Looks like it was time, eh?

Car is a 2004 4.8is. ~47k miles.

Much smoother idle. Thought it's very warm today- nearly 60.

Wow.. Mine didn't look that bad. Glad you were able to swap those out in time.

Yeah. I never did have smoke at idle or any time. I had rough idle. The worst was a couple weeks ago when the temp was in the 20's (F). The idle did not smooth and it ran rough for a good bit. After it sat for awhile, it ran fine. I am betting that was frozen CCV. I am glad I didn't blow a gasket. I am considering making these a maintenance item. Thinking every 2 years, but not afraid to run through a couple each year if it's necessary.

Cheap DIY fix for a seasonal headache.

Is this the 'fix' regarding the notorious blue smoke on 4.8is that every one speaks of?

Mine looked the exact same last night as I was too getting a rough idle. So I swapped them out and drove truck and it was smoother, but not fixed until I remmebered to take the 2 ccv hoses off and clean them out, THEN it ran smoothly.
Super easy fix and yes I agree, a yearly maintenance check and its soooo easy to replace all 4 parts, or at least clean out the hoses. Just don't be surprised if you break the rings holding the hoses in place, I did and I was gentle :(