Help me find the source of this oil leak

Looks to me like the exact same spot!

I did a front main seal, on the other side of that bulge is the high pressure oil feed. It leaks while hot and running. For me its not a lot but it coats my undertray.

Edit - Mine looked like yours until I pulled the radiator and front end while doing both headlights form Audi and a front bumper respray. I cleaned the crap out of that engine with shop towels and q-tips. My OCD got the best of me.

I feel like my active leak is coming from a different spot. When we had it on the lift, we had to reach up with a cloth on a stick to clean it. But at that time I could see oil fill the Torx well, and we couldn’t get it all out.

For the amount of oil on the ground, it seems like the recent pics are still relatively clean––unless it’s leaking right at the TORX bolt and not from the seam above.

From the seam

Originally, I thought it was only leaking from the driver side, but now that I’ve done a better job keeping the leak from traveling across the coolant pipe, it seems to be from both sides.

I think Ed was right. I’m looking back at some older pics when I had the main crank seal replaced. I see this mess around the oil cooler which can’t be all from the crank seal.


By comparison, that crank girdle looks relatively clean.

Looking at that shot, you can tell no oil is coming from the crank, rather it is hitting the crank and being flung all over the place with the majority of it to the oil cooler side.

There also does not appear to be any oil from the front of the valve cover gaskets or girdles.

There is a ton of oil at 2 o’clock on the picture, but the distance it has traveled across the head seems to indicate it had some serious force behind it (aka the dampener). It also appears to travel upwards on that side, reinforcing the idea that it is being moved against gravity.

I would still snake a cam up the right hand side of the valley. It looks dark a little too far back in there, but that could just be the camera.

For sure, if they have never been done, I would strongly suspect the oil cooler. That first photo looks similar to, but worse than mine. The tell tale is the significant amount of oil heading down the lip on the front of the engine below the cooler. If you are handy enough to get the nose off, you would have a much easier task of ID’ing what’s going on and conducting any repairs.

Ed

Id agree with IIiejk that the cooler seals need to be done, it leaks to the rear and to the front of the alternator, but doesn’t flow to driver side (US).

If you also have flow on the thermostat side, clean it up really really good, and run paper towels along the sealing surfaces of the crankshaft girdle near the thermostat side. Even at rest it should flow from pressure between the filter housing and the main oil galley. Theres lots of pressure here, and if you’ve had leaking oil filter housing seals this degrades this area further.

The bad news is, all the seals are generally going as these engines poor pcv causes much pressure in the crankcase failing seals left and right. They age and compress allowing oil to seep, compounding the issue is when oil leaks it degrades the sealant allowing more leaks.

BTW, the following did not work but oyu get the idea.

I’m going to attribute all the leaks on the pass Side to the oil cooler O-rings.

But I’m still trying to track down the source of the driver side leak, which is mostly reaching the ground from the bottom lobes of the water pump (see photos above). I did take another video this morning and saw oil collecting on the lip of the oil sump pan. The video begins at the water pump where it connects to the coolant pipe, and then pans to the driver-side, ending at the thermostat.

Can anyone tell me what is above the waterpump/thermostat in that areas? Is there a gasket or seal that I can look at?

Here is a shot of that corner of my mostly reassembled engine from last year.

Other than the valve cover, the o-ring for the cam sensor can be a leakage point. There is also a seal where the waterpump driveshaft goes through the upper oil pan.

Here are some closeups of that area. In the two cases of oil on the bottom of my engine, one was oil from the passenger side (oil cooler O rings) migrating across the bottom to the right side. The current leak is from the oil filter housing O rings migrating through the valley down the front of the engine. All of these shots have oil from the oil filter housing.

Let me know if you need any other angles or perspectives.

Ed

Thanks for the additional pics. I’m gonna study them later. But it does look like removing the SAI system will clear up some of the congestion up front.

I’ve had the problem with the oil filter housing before, and replaced the gaskets about 4 yrs ago. I’ve seen some oil sludge at the base with the borescope, but it doesn’t seem like the mess I had before.

My impression is that the oil from the valley will drain through this hole, was that the case for you? This pic was from a couple weeks ago, but it seems pretty clean.

Does it ever leak at the SAI valve?

No leak on my engine there. And yes that is exactly where the oil comes from.

Can you get a scope to look from right behind that hole back up into the valley one section at a time? You should be able to tell you have an issue from the oil housing pretty quickly. If there is no river of oil extending from the housing to the front of the valley it is unlikely to be coming from there.

Also from your picture there is either an old oil stain or current right below the hole, with a slight stain around it. Could this be left over stain from years ago? Only you know the answer there. If that was on my car, I would be suspicious since there would be no way I would leave that kind of evidence from a previous leak (mainly so I could tell if it was leaking in the future.

Ed

I’m seeing oil collect around the water pump––on the bottom lobe of #2 and also on bolt #13 from the diagram above.

Am I correct that gaskets #3 and #5 would only leak coolant?

Would it be possible to leak oil from o-rings #10 and #11? Could this be the source? At the very least, those 2 o-rings are cheap to replace with the front-end off, right?

Yes 3&5 would only leak coolant.

Yes 10&11 could leak oil.

Yes, you can pull the WP and replace those O rings with the front off.

Ed

Ed,

I just received the intake flaps. I’m so grateful for them. I’m gonna have the car opened up as soon as the radiator comes in––maybe in 2 weeks. I’ll let you know how it all shakes out.

m

Ed
How did you manage to remove the top inner half of the IM, the one that the flaps is connected to?

I never did. I used a beat up screw driver to forcibly separate the flap holders from that piece.

I think it was Justin who indicated it may be epoxied in place. I still have the IM, if I get a chance I will grab it from my recycle pile and do a little more damage to confirm how it is kept together.

Ed

No problem Mix, I am a true believer in Karma and that what goes around comes around. I wish everyone operated that way!

Good luck and I will be interested to hear how you do.

Ed

I’ve got the front end off again, along with the IM this time. I can definitely see oil in the valley—the oil filter gaskets are gonna be replaced.

Strangely, the drain hole in front is still clean, so maybe the leak isn’t big enough to make it out?

Apparently, there was also an oil leak at the Driver-side, intake Cam solenoid. Can you order new O-rings for these? Or do you have to just replace the solenoid. It hasn’t popped up as a troublespot on the OBD scan.

Gonna add more pics once the oil-cooler and water pumps are out.

I replaced these solenoid o-rings last month when I first got things torn down. I ordered them through ECS but I’d imagine you can find them through a variety of vendors as well. OEM part# is WHT002789.

As suspected, there was a real mess around the oil cooler and the o-rings were hardened. I hope I can definitively say that the pass side oil leak has been fixed with new o-rings

Also, found oil in the IM. Is this a clear sign that the oil separator membrane is torn?

And while there has been no drop in the PS fluid levels, there is (again) signs of some kind of leak at the top of this pressure hose. Not so much that it reached all the way to the bottom, though. Is this just a watch and top-off fix? (Cause I won’t be able to get a replacement in time)

Also, looking for new o-rings for the coolant pipe. Does anyone have part numbers? The number for the pipe appears to be PN 4F0121070H

And finally, the bottom edge of this hose is torn at the hose clamp, is it wise to cut 1cm off and then just reuse it? Cause I might not be able to get a replacement in time.