[jbash87]

2006 330xi oil leaking...

I've been getting oil leaking onto my exhaust manifold for quite some time and I am tired of smelling/seeing it. The dealership claims that it is a crack in my cylinder head and quoted $7000

Valve cover gasket was replaced about a year ago, and looks to be intact. I do see some significant oil build up in certain places as shown below.



The wire with the clear sheen of oil on it is the O2 sensor. Not too sure what the diamond shaped piece of the engine is??

[Efthreeoh]

I don't know what that diamond shaped part is either. It's some kind of port. I've seen pics of it open, but with no real explanation of what it is. RealOEM shows it as a "cover lid". But it does look like the gasket for it is leaking on your car. I doubt the head is cracked, but if it is, then it's cracked right by the mystery cover. If it is cracked there, then I'd locate the crack and take the car to an automotive machine shop and have them weld the head right there on the engine. But it is possible the valve cover is just leaking again. Getting the valve cover back on when replacing the VCG is a real bitch and the installer may have damaged the new gasket reinstalling it. When I did my VCG I used Permatex sealant to make sure my gasket didn't leak again.

If it were my car, I'd buy a new cover lid and gasket, clean up the oil mess with brake clean, install the new parts and keep an eye on it. The parts together are less than $10. Items 9 and 10. If it still is leaking after a few weeks of driving, then I'd clean it up again and inspect the area for a crack in the head and weld it up if there is one. To weld in that area, you may have to unbolt the engine mounts and lift the engine up a few inches so you can get a TIG welding gun in there. The DIY for doing the oil pan explains how to unbolt the engine mounts and lift the engine. Lastly, if there is no crack and the cover lid is not leaking, then I'd go for a new VCG and use P-tex on it. Here are the part numbers for the cover lid:

[2002]

The diamond shaped port from the crank case is for secondary air circulation. It is used on Super Low Emission Vehicles (SULEV).

[GoRomeo]

Originally Posted by Efthreeoh

I don't know what that diamond shaped part is either. It's some kind of port. I've seen pics of it open, but with no real explanation of what it is. RealOEM shows it as a "cover lid". But it does look like the gasket for it is leaking on your car. I doubt the head is cracked, but if it is, then it's cracked right by the mystery cover. If it is cracked there, then I'd locate the crack and take the car to an automotive machine shop and have them weld the head right there on the engine. But it is possible the valve cover is just leaking again. Getting the valve cover back on when replacing the VCG is a real bitch and the installer may have damaged the new gasket reinstalling it. When I did my VCG I used Permatex sealant to make sure my gasket didn't leak again.

If it were my car, I'd buy a new cover lid and gasket, clean up the oil mess with brake clean, install the new parts and keep an eye on it. The parts together are less than $10. Items 9 and 10. If it still is leaking after a few weeks of driving, then I'd clean it up again and inspect the area for a crack in the head and weld it up if there is one. To weld in that area, you may have to unbolt the engine mounts and lift the engine up a few inches so you can get a TIG welding gun in there. The DIY for doing the oil pan explains how to unbolt the engine mounts and lift the engine. Lastly, if there is no crack and the cover lid is not leaking, then I'd go for a new VCG and use P-tex on it. Here are the part numbers for the cover lid:

Dealers are a rip off! Get out of there and consult with an Indy shop.

Regardless, check for broken bolts before anything. I have oil leak, but mine is due to 2 broken bolts. Try to see if you can turn them with your hand. If you can, most likely are broken.

[Meeni]

Since you have a 330, there is also the oil separator that could be the source of that oil.

http://www.pelicanparts.com/BMW/tech...eplacement.htm

[Efthreeoh]

Originally Posted by Meeni

Since you have a 330, there is also the oil separator that could be the source of that oil.

http://www.pelicanparts.com/BMW/tech...eplacement.htm

The oil separator is on the other side of the engine. The OP's leak is on the exhaust side.

[Efthreeoh]

Originally Posted by 2002

The diamond shaped port from the crank case is for secondary air circulation. It is used on Super Low Emission Vehicles (SULEV).

Thanks for the info. I looked it up on RealOEM.com under the N51. Interesting.

[jbash87]

Thanks for the responses! I'm going to try replacing the gasket and cover like Efthreeoh has suggested. I almost couldn't believe it when the dealership said I had a cracked head. I would have thought there would be some sort of performance issues that would go along with that and have yet to notice anything but some burning oil.

Hopefully this fixes things.