2002 x5 3.0i CCV issue?
 

I just recently purchased an 02 X5 3.0i with 86,000 miles as a daily driver so the M5 wont have to get up for daily duty. It is sienna red on beige with sport premium,and winter package. I love the car but have noticed since it started getting very cold here in Reno NV that there is a yellow sludge buildup on the oil cap and I have tried to go for about an hour drive at freeway speeds but it still wont go away. I haven't replaced the CCV or any related hoses either. Why wont it go away!?

Sorry to tell you, the Mayo will never go away. Water vapor is a by product of combustion and the crankcase is drawing outside air with moisture in constantly.

Mayo is NOT a BMW specific feature or option, albeit a "standard" feature or option.

A few main factors impact the Mayo:

1. Engine coolant temperature, I estimate that about 30% of the vehicles on the road have soft thermostats and do operate at the proper operating temperature.

2. Large oil sump takes a 3-4 times longer to come up to temperature than the engine temperature. Short drives are NOT good when you have a large oil sump.

3. Contaminated oil. Moisture caught in the crankcase or oil that has not been "cooked" out. I always start off the Fall season with fresh oil in all my vehicles regardless of mileage, however, I specifically have timed my oil changes for the Fall and for the most part this falls in line with my driving style.

4. Crankcase seals and CCV that is degraded. Cracked or leaking CCV hoses, leaking valve cover gasket, cracked valve cover, leaking oil fill cap and leaking dipstick and dipstick tube O-rings. I suggest a proactive replacement of the CCV system by the vehicles 8th birthday. The parts may last longer, however, it is not if, but when the CCV and hose, valve cover gasket and other things need to be replaced. If you wait, like anything you will end up having to do "emergency/non scheduled" repairs usually in the Fall or Winter. Plan your repairs, you can control the cost and schedule.

Another major part of Mayo is MANAGEMENT.

Suggest read read these links -

Bit worried about mayonaise... - E46Fanatics

Check your thermostat/engine temp - Report In - E46Fanatics

I have covered ALL things M54 in great detail on other forums with thousands and thousands of views and help many forum members resolve problems like this.

Enjoy your E53, but plan on a fair amount of PM to keep the vehicle reliable.

Fuel pumps, intake air path and vacuum leak problems, valve cover can OFHG, cooling system are all key areas to focus on.

How often are you changing the oil? How often do you drive the car during your daily commute? If you are driving less than 30 minutes for your commute, you should try changing your oil more often than the recommended mileage by BMW. I change my oil every 5,000 miles. I avoid short trips with the X5 such as taking the kids to school. A little exercise never hurt anyone.

The "Mayo" will go away in the summertime. You live in a desert so the air has less moisture compared to other location.

I'm doing this next week: The Permanent M54 CCV Delete - E46Fanatics

Sourced the aluminum valve cover, oil dipstick tube, connecting hose, and plastic cover that goes on top for $150 from some guy on CL. Valve cover gasket set for the M56 plus a few other parts are on the way. Rebuilding VANOS at the same time.

I imagine rebuilding the VANOS, replacing my CCV system with a superior solution and fixing my leaky VCG all at the same time will provide quite an improvement in engine response.

I change the oil every 5,000 miles. I might do one more hot oil change soon.

Hi guys, as mentioned it in some other tread - yes, I totally agree, CCV system is complete failure of industrial design, huge "-" to BMW. There is no way they could not place it extended to more service friendly area rather than shovel it where they did. I won't speak for functionality, as if it serves for 75,000 miles run, if it does it's job for average 5 years and cost $200 - I can live with that.

I would do a little troubleshooting first. It could be a simple vacuum leak. With the engine running remove the oil filler cap. There should be a vacuum if there is no leak.

Problems with the CCV systems are far more prevalent where winters are extreme. I wouldn't consider Reno having severe winters.

It is not how long a drive you take. It is about driving long enough that the oil temperature has been at normal operating temp-should be 20-20 minutes.

I haven't touched the CCV system. My input is that the design is fine. I do change my oil every 5000 miles and Texas winters are close enough to call them Michigan summers.