Is it worth it to Clean the CCV valve?

[theblue]

you should see my A3's cap... I could fill jars of miracle whip with it if I kept cleaning it out. Still running strong at 120k

[FCBuff]

Hmmm, OK then. Anyway, a new CCV seems to have "fixed" it for now.

FWIW I had 3 A4's and never have I seen it

[RickM5X3]

What's the consensus; can you rehabilitate a CCV? I recently bought a 4.8is and immediately drove it for 13.5 hours home, only stopping for gas. Would this have the effect of cleaning out the CCV if there had been any build up in there, or is this not how it works?

[JCL]

Originally Posted by RickM5X3

What's the consensus; can you rehabilitate a CCV? I recently bought a 4.8is and immediately drove it for 13.5 hours home, only stopping for gas. Would this have the effect of cleaning out the CCV if there had been any build up in there, or is this not how it works?

Not how it works. It is remotely mounted so doesn't get hot enough. It is a canister that crankcase fumes are vented into, so it doesn't have oil circulating through it. It separates the oil mist from the fumes, and the resulting oil drains back into the sump. Unless it is frozen shut by condensate paste that has built up over time, and then frozen.

You can rehabilitate it by manually cleaning it out, and depending on the model, by replacing the diaphragm if necessary.

[Gurjit]

V8 ccv is ontop of valve covers ur condensation should b taken care of after that drive, easy to remove just pry 6 tabs and pull off, i cleaned mine and the idle got smoother

Also open the 4 way hose and blow air through it to get the oil out if there is any and check ur intake maniffold for buildup

[LeiZ]

My own experience: 2 years ago, the car caught on fire due to frozen CCV (pressure built up and pushed the oil out of valve gasket). Then I have the entire CCV and hoses replaced. This year, I found the yellowish stuff again.

Originally Posted by FCBuff

I here you, that is the conventional wisdom.

However, I will tell you that I know all of that and have observed that, having just replaced the CCV this fall, there is no Mayo under the fill cap after short trips. Likewise there is no longer any significant oil loss. I drive it 300miles round trip skiing weekly, but often lots of short trips in between. It reached a point where it did not matter if I drove it for a long drive or not, there was always mayo. I never had the mayo before, and all of a sudden it started. I also have driven multiple cars with similar driving and never have I seen "mayo" formation, this includes 3 other BMW's. It seems to be unique to the M54 I don't pretend to completely understand it, but replacing the CCV solved it! Hopefully for a good long time too, since I don't want to have to replace it again anytime soon!

[ArmyX5]

Originally Posted by FCBuff

I here you, that is the conventional wisdom.

However, I will tell you that I know all of that and have observed that, having just replaced the CCV this fall, there is no Mayo under the fill cap after short trips. Likewise there is no longer any significant oil loss. I drive it 300miles round trip skiing weekly, but often lots of short trips in between. It reached a point where it did not matter if I drove it for a long drive or not, there was always mayo. I never had the mayo before, and all of a sudden it started. I also have driven multiple cars with similar driving and never have I seen "mayo" formation, this includes 3 other BMW's. It seems to be unique to the M54 I don't pretend to completely understand it, but replacing the CCV solved it! Hopefully for a good long time too, since I don't want to have to replace it again anytime soon!

The majority of M54 Engine owner will disagree with your conventional wisdom, myself included. The fact that you drive your X5 300miles weekly is preventing you from accumulating the Mayo, also the type of short trips made can make a different. If you drive to the store and get back in your vehicle after 15-30 minutes and park your vehicle in a garage, your engine maybe still warm and not condensation is formed, but if you drive to work days after days for 15 or so minutes/miles and leave your car outside, you will see the Mayo. For some of us it may take 2-5 years to see the damage that a frozen CCV can do to your car. Someone mentioned that the Mayo is not harmful and he is correct. It is the freezing of the Mayo as mentioned by JCL that will pressurized your engine make it blow up.