I've had an oil leak in my 2002 525i sport (@151,000 miles) that I THOUGHT was fixed...in beginning of February, I had the following items replaced: - valve cover gaskets and bolt seals - oil filter stand gasket and seal kit - vanos oil line and seal rings However the gosh-darned thing is still leaking!! I can't say how much for sure but I know for certain that I get the "CHECK ENGINE OIL LEVEL" message far sooner than I should expect and I have to put in a quart or more. Can anyone out there help a brotha out?? What else should be done here? I hear a lot about a CCV valve...what is that and does it have anything to do with this issue? I appreciate all input...thanks!
Wish I knew your engine in detail to offer up some suggestions - try some searches on bf.c and see what comes up...
Not sure if this is helpful or not but it's a 2.5 liter 6. Inline, I believe. Naturally aspirated (not a turbo) and the car is a 5-speed stick with the sports package (if that matters). Engine code: N52, I believe (?)... I've been on bimmerforums.com and there's so much information (and I'm soooo NOT knowledgeable!) that it was hard for me to determine what the specific issue could be, given what I've already had done to try and correct the issue to-date.
Diagnostics are always the hard part Frank - pop the hood and take a good, long look at everything you can see under the hood, with a super-bright flashlight. Take your time and look slowly, look for shiny & wet, & look _everywhere_ that you can see; if you're losing a couple of quarts in a fairly short period of time, that would seem like a substantial enough leak that you should be able to see some indication from where it's originating. Use realoem.com and a Bentley manual to edumacate yerself about what parts are what, that may help with the knowledge-building part. If your leak is from the underside or low on the engine, it may be difficult to see from looking topside. You'll have to decide for yourself if you want to get under the car to start looking at things (using safe jacking methodology, etc. etc.). You might find it useful to use an inspection mirror to get a look at the underside of things. http://www.harborfreight.com/telescoping-mirror-7361.html http://www.harborfreight.com/2-inch-mirror-with-flexible-shaft-97217.html Presumably, your engine is the M54B25 - http://en.wikipedia.org/wiki/BMW_M54 The CCV valve is the Crank-Case Ventilation valve. Not being an expert on the subject, I'd suggest calling a club TSA or Bavarian Autosport and just asking whether the ccv system might be related to your issue, and separately, what the worst implications for your engine are with CCV problems. http://blog.bavauto.com/4791/bmw-pcv-valve-crankcase-ventilation-oil-separator/ http://blog.bavauto.com/5434/bmw-m54-6-cylinder-crankcase-ventilation-pcv-diy-325i-328i-330i-525i-530i/ Here's a long thread on a difficult-to-identify oil leak _after_ replacing their ccv system - http://forums.bimmerforums.com/forum/showthread.php?t=1629018&highlight=m54+ccv+valve A nice diy, useful info (M52TU) - http://forums.bimmerforums.com/forum/showthread.php?t=1528460&highlight=m54+ccv+valve an M54 ccv diy writeup - http://forums.bimmerforums.com/forum/showthread.php?t=1376457&highlight=m54+ccv+valve CCV info - http://www.bimmerfest.com/forums/showthread.php?t=536317 It would appear that, perhaps, it's advisable to replace the oil separator valve as well when doing CCV system replacement. http://www.ecstuning.com/BMW-E46-330i-M54_3.0l/ES25780/ http://www.bimmerfest.com/forums/showthread.php?t=187676 Keep in mind none of that may be related to your oil leaking, but given your mileage, you may want to look into it unless addressed earlier in the car's maintenance history - or, perhaps it is related, no way for me to know! Good luck! Just FYI - ICV = Idle Control Valve PCV = Positive Crankcase Ventilation OSV = Oil Separator Valve
Frank, I believe your motor is an M54B25. Have you actually seen any oil on the underside of the block or collect in the pan under the engine? After an oil change, how many miles do you go before you need to add a quart? how often do you change your oil?do you enjoy spirited driving (i assume from driving a standard, i applaud you!) or have a more relaxed driving style? depending on the answers, you may not be leaking oil at all. additionally, since the oil light is multi stage, what behavior does it exhibit? if it turns on shortly after startup up and is yellow then goes away, it indicates that the sensor itself is busted.
Thanks MGarrison and two30grain for your very detailed and helpful responses. This is why I LOVE this club! An update - had the car in for a "look-see" at my local "stealer" (what can I tell you - they are right around the corner from work and they offer shuttle service right to the office!)...they were fixing a headlight bulb and I asked them to check into my oil leak issue. Service guys said no leaks or wet spots, nothing codes, all seems fine. They seem to think the indicator might be dying, I don't know...last time it went on the car did need oil...I put oil in and hadn't seen the indicator since. I do put a LOT of miles on the car; perhaps I'm using not losing? At any rate...thanks again guys!
@ 150k, some oil usage might be expected, but if you're using more than a quart every 3k, you might want to do a compression test - one of the threads I found that I didn't post a link to was somebody who had some kind of piston-ring problem that was tied to some other problem and showing up initially as excessive oil consumption. Also, take a look yourself, just as a double-check on what the dealer's telling you.
I put some flattened-out cardboard under the whole front-end of the car this past Wednesday evening and let it sit overnight (@9 hours). Not one drop of oil was found on the cardboard next morning. Interesting. Next oil service I plan to have the indy mechanic perform a compression test.
It occured to me that i didn't answer your questions...sooooo... I have not seen any oil on the underside. Haven't checked the pan. Didn't notice the amount of miles before adding...sorry! I have the oil changed every 3k-5k. I totally enjoy spirited driving and yes, the manual 5-speed gets lots of work! Wouldn't say I'm a "relaxed" driver by any stretch LOL !! It's not the multi-stage indicators, it's the message I get under the speedo/tach that reads out "Check Engine Oil Level" or something to that effect. In the post above, an update...a "cardboard test" produced no droplets or evidence of oil leakage, so I'm going to go the route suggested by MGarrison - a compression test and see if I'm actually consuming the oil somehow, since most of the leaks appear to have been corrected. Thanks!
Possibility of a problem with an oil level sender or sensor? Or, when you get the message, does the dipstick actually show you're low on oil? How much - a quart?
My bet is, like you said, you are using, not losing. If it is just one to 1.5 quarts in a 5k oil change interval, i think you are doing pretty well at over 150k. Im also going to bet that your compression numbers are all going to be within range of each other. Good luck and let us know what the result is!
I think you are correct, sir! YESSSH!! It's more frequent than 1 - 1.5 quarts in the oil change interval so there is definitely an issue with *something*. I'll update y'all when I bring it in for service (probably in the next few days or so)...thanks.
