View Full Version : Calling all M54 Owner's RE: Crankcase/Hydrolock

01-16-2009, 12:03 PM
I know we've talked about this issue a lot here, but I would like to know if and who's experiencing problems with sludge build up and noise from their crankcase/oil seperator this year?

Does anyone have any other recommendations other than driving the car hard after warm-up? We've been experiencing this with my brothers car, and even after a full day of hard driving, the noise comes back today, sludge is apparent also(oil change done 2 weeks ago and replaced with insulated crankcase + lines last year). Is this problem with ALL M54's or a select and what are the odds of having the engine overflood? Also does a CAI induce this?



01-16-2009, 04:52 PM
i've just been driving for longer than i usually would. also long trips help. you want to get the oil at operating temps for long periods at a time. then you shouldnt have any problems.
you should only have issues if your taking repeated short trips.

01-16-2009, 08:38 PM
has this ever been an issue with s52's?


01-16-2009, 09:12 PM
No problems here in my 330 nor with my father's 330. He drives his car barely even 5 kms to work and the engine doesn't even have time to get fully warmed up - yet he hasn't experienced in problems in the 3 yrs he's owned it.

Dunno what's up with your brother's car, even though you had the crankcase taken care of last year. Try posting on Fanatics for more info (even though that shithole is more of a show and shine forum...).

01-17-2009, 12:24 AM
^See that's what I was thinking. Not all these engines have this problem and I wanna figure out why. I'm thinking it could be the CAI. Anuk did you put your intake back on or are you still using the stock one?

01-17-2009, 12:36 AM
I still have my Gruppe M thingy on there. Where are you seeing the sludge build up?

01-17-2009, 01:08 AM
On the oil filler cap and on the dipstick... I had the car again today and after a lot of hard driving I opened the oil filler cap and it was dripping water and the sludge was bubbling! So I know it's evaporating... We also do drive long distances at least 3-4 times a week, but the condensation keeps coming back! I don't know if I'm being too pre-cautious or anal, but I would think most owner's would/should also notice this.

01-17-2009, 02:03 AM
Seen this problem millions of times and alot of 2.5L and 3L engines both in the 3's and x5's, just this week alone ive done quite a bit of crankcase vent system due to low climate temps. these engines develop alot of moisture on cold start ups and depend on the condition of your crankcase system, the moisture will be burned off while driving/idling. Best thing to do is drive the car as much as possible, and some people after a long drive over night leave thier oil cap off so that the moisture escapes the engine instead of staying in the motor and freezing the crankcase system. Hope this helps in any way

01-18-2009, 03:06 PM
some people after a long drive over night leave thier oil cap off so that the moisture escapes the engine instead of staying in the motor and freezing the crankcase system. Hope this helps in any way

never heard of this..seems logical enough though.

and michel, what does the pcv noise sound like?

01-18-2009, 07:11 PM
^Theres 2 noises actually.. the one I usually hear is a whistle, kind of like the intake, but much louder and goes away after 3000rpm. The second noise I hear is usually around 2000rpm, which sounds a lot like when you apply the brakes when they're rusty and they squeal.

After my two days of distance driving, I havent had problems since yesterday and today... then again it's not as cold as it was last week.

01-18-2009, 07:20 PM
Is the whistling sound an actual whistle, or is it more of a whirring sound?

01-18-2009, 09:21 PM
^Whirring! that's the word lol...

01-18-2009, 09:41 PM
Does this whirring speed up as you rev it until about 2K where it gets drowned out, or is it constant? I noticed my car has a very slight whirring when it'd idling and cold.

I'm not sure if that's the symptom of a bad PCV, but I had that same thing on my E36. It turned out to be a bad alternator pulley - thankfully, a cheap fix! Wonder if it's the same issue for us or if it is more serious...

01-19-2009, 12:16 AM
no well for me this noise comes at certain RPM's (never above 3000rpm tho) and only for a brief moment. It doesn't speed up or anything. And it goes away completely when the car is warm. Mind you, this ONLY happens when its ~ -15 + outside.

Anuk, just check your oil cap for the yellow sludge. your issue might be pulley like your sayin.

01-19-2009, 01:16 PM
change it :) u get that farting noise??

01-19-2009, 02:33 PM
^hahah noope, no farting noise... We will be changing it soon, thanks!

01-22-2009, 09:40 AM
My understanding is that the yellow sludge is a combination of the moisture mixing with the synthetic oil............. we've had the joy of experiencing hydrolock in the middle of the highway. Anyways, the thing was fixed and now I drive it because my wife's trips are really short. And I still get yellow guck.......... mind you not as bad anymore. BEfore, there use to be A LOT ......... even on the dipstick. Now I just get a bit on the cap.

It's a BMW design failure with the oil seperator valve/line................ not covered under waranttee. Thanks BMW. Even the insulated fix guaranttees nothing apparently.