Where is the oil going?

Over the past 15,000 miles I've added about two quarts of oil due to being low. I changed the oil today and poured the old oil back into the used containers. I put in 6.5 quarts, but only drained out about 5.25 quarts.

I've never noticed any smoke or oil burning smells and I've never had any oil leaks below my vehicle.

Here is the backstory on my vehicle: It currently has 114,000 miles. At around 88,000 I noticed that it was losing oil by using the onboard electronic dip stick. I added a quart. A couple of months later at around 95,000 miles I changed the spark plugs and found oil on plug #4 or #5. I took this in for service around 98,000 miles. The dealership, while under CPO warranty replaced the valve cover gasket and the oil filter gasket to fix the problem with oil leaking into the spark plug holes.

The oil and filter were replaced around this same time at 98,000 miles. Since then, I'm now out of warranty and have put in about two quarts of oil due to being low.

At 111,000 miles, Nov. 2012, my fuel pump went out and I took it to the dealer to be replaced. While it was there I had them look into my lose of oil. They said they found nothing and no signs of a leak anywhere.

I've noticed since Nov. 2012, that I've been a little low according to the electronic oil meter.However, today when I changed the oil I decided to pour the old oil back in the containers just to see how low I was. I was about 1.25 quarts low.

Any ideas on where the oil could be going? Again, I have no puddles beneath the vehicle, no burning oil smell, and no smoke from the exhaust.

Thanks,

-w

Hmmmm....My first impression is that I think your dealer didn't do any digging.

If I were you I would do the following:

1) crawl under car and remove lower modesty cover (four 17mm bolts on stiffening plate and about 12 8mm bolts). Do this to look for where the oil is going...it has to be somewhere and it will always find its way to the lowest spot.

2) remove upper engine modesty cover (its what your oil cap is in). 4 torx screws and it pull off. Your looking for the following:

-valve cover leak
-oil filter housing leak
-since you have an 07 there is a solenoid on the valve cover that has also been reported as a leak source.

-the final place to check is to pull your spark plugs...probably due anyway at 111k.

3) if none of the above doesn't point out a leak I would suspect a faulty oil level sensor but you just measured the drained oil so i would send into blackstone for analysis....I would fear leaking head gasket.

The only other possibility...but haven't heard this on a na n52 with out direct injection is really mucked up combustion chamber with cooked oil...but like I said that's common with the turbo...not a na motor....

Keep us posted...my 09 is similar milage 109k and doesn't burn any oil.

Only thing I could think of (after I read brian's post) was bad CCV??

Technically you're within the specs provided by BMW, which is up to a litre of consumption every 2000km (1200mls) is considered "normal"......but then again there are a lot of factors that affect oil consumption such as environment, driving habits, etc....

Originally Posted by AzNMpower32

Technically you're within the specs provided by BMW, which is up to a litre of consumption every 2000km (1200mls) is considered "normal"......but then again there are a lot of factors that affect oil consumption such as environment, driving habits, etc....

I, too, have seen this or similar figure for BMWs and other cars. However, my car can go 7,000 miles and not consume any measurable oil. What they probably mean is that 2000 km with oil loss is either not important or difficult to find the source of the loss so don't blame the dealer if they give up.

Just out of curiosity, what kind of oil are you using? My Subaru had a problem with Mobil1 5w-30. I was having to add a quart or more every 1000 miles, but I could never find a leak from anywhere and no smoke out the exhaust to indicate burning oil. I switched over to Pennzoil Platinum 5w-30, and I rarely have to add any oil between my 5k interval changes now. Some WRX guys have the same problem with Mobil1 and some don't.

Originally Posted by wil33562

A couple of months later at around 95,000 miles I changed the spark plugs and found oil on plug #4 or #5.

If you have a 2007 or newer X3, it might be worth replacing the $30 USD Valvetronic gasket and this is something you can easily do yourself. Below is a picture from a DIY I am working on which shows the gasket. If this is bad, it would cause some oil to appear in one or two of the center two plugs. Mine had some oil there; however, I never have to add oil to my X3 between changes at ~80k miles.

mchova01,

I'm very interested in the DIY you're working on. My daughter and wife both drive N52-engined BMW's and both have about 90k miles. The X3 had a new valve cover gasket put in when they replaced the lifters (ticking issue) but daughter's car is definitely due for the gasket change. Looking forward to it.

this is why you should change oil every 7500 at the latest. all engines burn oil but at different rates. I add a quart over that period, yours seems to take a bit more. you will not see any smoke coming out until the engine is faked usually. your cats are removing most of it. take a look at cold starts if there is any smoke.