[bryanbrian]

My N20 engine, 2012 328i, seems to have an oil leak on top of the engine. There is oil collecting just in front of the oil filter. See picture. It looks like it might be coming from the oil filter cap but I torqued it and there doesn't seem to be any oil leaking there. Any ideas? Also, what is that thing in front of the oil filter?

[Billfitz]

It's probably the oil filter housing gasket. They seldom make it past 80,000 miles. That 'thing' is the oil cooler.

[bryanbrian]

Thanks, engine has 110,000 miles.

[Fliplegend]

Could also be coming from the oil filter cap if the o-ring that goes around it was improperly installed during the filter change. That oil covered alternator is worrying.

[bryanbrian]

Originally Posted by Fliplegend

Could also be coming from the oil filter cap if the o-ring that goes around it was improperly installed during the filter change. That oil covered alternator is worrying.

mmmm could be. But I seem to like to do the most complicated repair first.

[Fliplegend]

Ideally, you would want to clean all that oil up to see where it's actually coming from. A new oil filter o-ring is just a tad easier than the OFHG. I'm truly hoping it's the former.

However, as I look closer, I am seeing oil on the upper coolant hose and pretty much when I see that, it's almost always OFHG.

[bryanbrian]

Originally Posted by Fliplegend

Ideally, you would want to clean all that oil up to see where it's actually coming from. A new oil filter o-ring is just a tad easier than the OFHG. I'm truly hoping it's the former.

However, as I look closer, I am seeing oil on the upper coolant hose and pretty much when I see that, it's almost always OFHG.

I took your advice and the oil is definitely coming out of the oil filter housing gasket. Looks like I have some work to do.

[Fliplegend]

Fortunately there is an excellent FCP write-up/video that walks you through it. Good luck!

[bryanbrian]

Originally Posted by Fliplegend

Fortunately there is an excellent FCP write-up/video that walks you through it. Good luck!

Yes, I watched the FCP video. Very very good one. After watching I realized that the leak could be from the oil cooler and not the filter housing gasket. So I just changed that part, which does not require you to remove anything else. During removal I noticed one of the bolts was not torqued correctly but I replaced the gasket anyway. So far so good, no leak right now.