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Q: Oil leak into cylinder. on 2002 BMW 325i

Theres smoke coming out my exhaust. My mechanic said that without taking the engine apart he could only tell that oil was leaking into the cylinder. However, I notice my engine has been starting to shake. While in park, the rev got extremely slow and the check engine light came on. I turned the car off and started it back up and the light went off. Are these symptoms related? What needs to be done?
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-from Virginia

Hey lioneljr, the same thing just happened to my 2001 BMW 325cic... garage kept well maintained 90k miles....and I know how seeing all that smoke can freak a person out. I sure was wondering what the...but then I did my homework

There is most likely nothing wrong with your engine. The part that needs repair is a simple thing outside the engine.

The PCV or in BMW talk Crankcase-Ventilation/oil seperator is most likely the culprit from all that I have been reading from a number of different BMW sites. (do a google or yahoo search on BMW and the phrase above) Apparently these devices are known to go bad a LOT, especially in cold weather, but can fail in non-cold climates too. Just the other night we had a weather freeze warning. On the 7th, at the advice of the TV weatherman, I remembered bringing the spring plants in that I had just two days earlier put out on the back deck. The next day, driving home from the office, was when the problem started with my car... but the PCV had probably been degrading throughout the winter.

There is a BMW service bulletin out on the problem instructing their service mechanics and technicians on how to handle customers presenting with the problem, but it seems they have never issued a voluntary recall... I think BMW is slipping. It seems water/condensation can build up in the oil seperator valve (ie PCV) or in one of the several hoses that connect to it and on an especially cold night or morning expand in the plastic and crack it or damage the valve. Oil then can leak back into the engine and exhaust valves and/or cylinders and cause minor or major problems depending on whether the PCV valve fails open or shut. Most often the problem is relatively minor resulting in the thick white/blue smoke you witnessed billowing from your exhuast pipe. If the problem were more serious oil would build up in your cylinders (and since a fluid is incompressible) your engine would have locked up and you would not have been able to start it at all. So thats the good news!!!

I have just purchased the BMW Crankcase ventilation kit part #11 61 7 533 from Bavarian Autosport
without shipping it came to $169 and the forum say that while it is a tough repair only because of where it is located, a competent do-it-yourselfer should be able to complete the repair over a Saturday.

The problem is so prevalent that they make an entire kit that includes the oil seperator valve (which looks like a plastic mechanical heart) and all of the hoses, elbows, and clamps since your old ones might be brittle or have holes that also add to the vaccum problem that can also cause the rough or intermittent idle and the check engine light. These new BMW crankcase valve kits are supposed to be Cold weather enhanced with insulation too.

If you take it to the dealer, not under warranty (my 2001 is nolonger under any warranty) it will cost you from $750 to $1000 for the total repair, parts and labor.

It seems to me such a ridiculous design that a part like this could fail in a way to destroy an engine without any warning in the worst case scenario or like yours and mine did thankfully with just an awful embarrassing thick plume of white smoke trailing out the tail of a seemingly first class auto.

I have owned a '93 BMW 325i and my '01 325cic , while I love the cars and the fun memories, I don't think I will purchase another one for this coming decade. I have had other annoying little simple and big costly things happen with the '01 vehicle that I nolonger believe BMW is the ultimate driving machine... its just corporate bottom lines and advertising now.

Sorry to end on a downer, but hope this helps you and others in the continued search for information.

P.S. from the statement of your mechanic in your post, I would recommend finding a better informed mechanic. Or talk to him about this and see what he says.
Yes the symptoms are related. Oil leaking into the cylinder can cause a misfire, and a misfire causes the check engine light to come on. The engine needs to be repaired so it won't misfire.
What about the PCV Valve? Does that play into the equation at all? And what should i expect to pay when getting my engine fixed?
I had the same problem. Most people say its the valve cover gasket and it may be. But my problem was more than that. If this has been going on for a while it will damage your valves. By the time you start noticing the problems it is already too late. If your luck you will be able to replace the valves and the seals and get on with your life. It will cost anywhere from $1600 to $2000. you will also need new spark plugs if they are fowled. Good luck.
Does anyone know when BMW started production using the PCV system that does not fail? I've seen a service bulletin dated 2009 but understand this problem may have had an earlier bulletin.

Does anyone know if you can tell if the car has an updated system (without removing the manifold)?
VertexBMW... forgot to sign in.

You may can tell if you can squeeze your hand small enough and close enough under the intake manifold to touch it. Poke it with a finger and see if you can feel the insulation. It is foam like material just like a beer cozy. It is really tucked away and hard enough to see, so I don't think you can touch it without removing things. You should be able to see it with a telescoping mirror and a good light, but the PCV/Oil Seperator is black and so is the insulation so it might be hard to tell without poking it.

I do not know when or if BMW has started production using the insulated PCV system. My guess would be 2009. It is better, but I doubt that it is fail proof. The system definitely needs a better design or at least more easily accessible. But in my opinion, when a $100 part has the potential to wreck a $10000 engine without warning that is insane. The general BMW design philosophy is what makes the maintenance and repairs so expensive!!! and why you see the BMW shift from solid engineering to slick advertising and the tease of first four years free maintenance. The car is a very good car and solid design such that nothing is going to happen to it in the first four years and maybe for a while after that, but around 60000 miles the design is cumbersome for maintenance so much so that if anything happens, and it will for the cars produced in the decade of the 2000's, repair is going to be very expensive and mainly due to the added labor time and effort it takes just to get to components.

I did my own replacement of the PCV/oil seperator as I partially described in the post above. It was not an easy repair and I wouldn't recommend doing it yourself unless you are very confident, competent, and calm. The car will fight you every turn of the screwdriver. It does not require any real special tools... ratchets, and drivers are about all you need. Extenders and goosenecks help a lot. But you have to take apart just about everything attached to the engine just to get to this plastic part... and I MEAN JUST ABOUT EVERYTHING. It is totally insane to be designed this way. On top of that everything blocks every other thing just enough that you can't remove a bolt without taking the thing blocking it completely off. A lot of the time you will be working blind, just by feel, so studying the diagrams and a Haynes manual in advance really helps. Mirrors and a good light helps too. Also a magnetic pick-up for the nuts you will inevitable drop. Be methodical about keeping track of all the parts you take off and do everything in the prescribed order and take digital pictures every step. The secret is just to walk away when you get frustrated and then comeback to it after a half hour or so.

The good part of the story is that after methodically taking everything apart, removing the old PCV/Oil Seperator and all associated hoses and replacing them with the new insulated version and then putting back all the removed components i.e. throttle body, intake manifold, dip stick holder (no kidding), electrical connections, etc., etc., etc., etc., etc., etc., etc., etc., etc., etc., etc., ... It ALL WORKED!!! I can't tell you what a relief that was.

I still own this 2001 325cic and since 2009 it has gone through two winters now with the new insulated PCV/Oil Seperator without any problems.

I love BMW's...I owned one for the decade of the 90's which is still on the road and looking good, I have this one from the 2000's which I will keep since it is a convertible and still looks new, and I am about ready to buy my primary fun car for this decade of 2011... but this time I am not sure if it is going to be a BMW, my heart says yes but my head says NO...they have been sliding and I experienced it in other earlier crazy maintenance cost at the dealership after the warranty expired in 2006 which is what made me start doing my own repairs in 2009 (I am not a mechanic, but fortunately from helping Dad in my childhood I am capable and I have the time)... but if you don't believe me on all of this take a look at Consumer Reports... it hurts to say, but there are better cars and less expensive too.
I picked up a 2006 X3 today, and it does have the insulation on the system, but frankly I don't know what that really will do. I do suspect I'll have the PCV issue. My typical driving is less than 5-minutes at a time, and in northern Vermont we are below freezing 5 or more months in the year, not uncommon to get to 20F below.

I sense you are correct about the trend with BMW. I own a 2007 Toyota Rav4 (Sport, V6, AWD). It is a dream car, really blows away the X3 (which has an automatic). On the highway I would say the Bimmer is more stable, but I have little issue with the Rav4 on the highway. I had considered getting a used Rav4, but the X3 is much much less expensive on the used car market, even though the price for new X3 were about 35% higher than the high end Rav4. Resale value is a function not just of reliability, but also cost of ownership. I suspect after about 3 years I may regret my decision - but maybe not, since I only drive 1500 miles/year.

By the way, the Rav4 using 87 octane, get around 27 - 29 mpg, the X3 using 93 get 20 - 21mpg.
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