likely there is no reason to replace the oil separator, just repair it. bend the tabs, and clean the lid, then seal it all up with ultra black RTV and bend the tabs back. no more oil in the air cleaner.

Upon further inspection, I have found a couple places where it is leaking, but not these leaks are not leaking fast at all. The places are both the oil cooler lines (the real ones this time) and the valve cover gasket. I know the oil cooler lines have the capacity to leak decently, but after letting them drip, there wasn't much oil there. I think the valve cover might be doing it, but it's such a slow leak. Unless it's related to my next thing:


I determined that the major oil leakage had to have come from the rear of the engine, because that's where the huge puddle is. I can't see well back there, at all. So I don't know where it's leaking from, but I tried to get a picture of the area. This is the picture, taken from underneath the oil pan looking down the car. The oil is dripping off of that arch thing behind the oil pan, but I can't see how it's getting onto it since everything is still covered in oil.

I appreciate all the help I've gotten with figuring out how wrong I have been. It's been a journey. I will be replacing the leaks I have found so far, but I still haven't found the big one which kinda makes it useless.

Was the oil cooler hot when the cooler lines were leaking, indicating that the thermostat in the oil filter housing was open?

That's a lot of oil spread all over the underside of the car. I would take it to a car wash, get under there with a sprayer and get everything cleaned off to see exactly where it is coming from. I'd do the same thing in the engine compartment.

There are a couple of plugged oil gallery passages on the rear of the block. A failure there would be consistent with the sudden onset of a substantial oil leak.

I didn't feel the oil cooler, I can do it again tomorrow to check, but I let the car idle till it was at 80 degrees Celsius. I do need to take it to get washed, but also can't drive much with this leak. I literally live a quarter mile from a car wash but last time I was there it was inop. So I gotta check up on that and hope it works again.

That's probably not enough for the oil cooler thermostat to open.

I doubt the oil thermostat open up at that temperature. You may have to partially block the radiator if you want to get it opened without driving fast or under a heavy load.

If it's leaking so much that you can't drive a quarter mile it should be pretty obvious.

I would check it with the engine running if you haven't. Look for the highest and furthest forward part that looks wet. Hose your engine off so that you can better visualize where it is coming from.

At least you have a rust proofing plan!

The leak seems like it had to have been the ventilation hose. I cleaned it out and the oil separator and it was completely normal. After some testing I took it on a 3 hour drive and nothing too dramatic happened. The small radiator hose started spraying fluid everywhere... but not the oil!

Are you saying that the pcv hose was pinched? Was there evidence of pinching? How much blowby does the engine have?

Which small radiator hose was leaking?

yeah, the hose had compression marks on it from where it was bent over the air filter housing. There wasn't much blowby in the summer, but now there is a significant amount.

It was the small hose that goes from the top of the radiator to the expansion tank.

That makes sense. Didn't you write earlier that the air filter housing wasn't sitting right on the mounts or something? That might pinch the hose between the housing and the hood.

Take a real close look at the oil pressure sending unit. I have seen more than a few that sprung a leak and the oil comes out in a fine stream and wont splash till it hits something. And when you shut off the engine there is no more leak.

Often, some major leaks wont appear until the engine is wound up and making more oil pressure. 2 bar may not be enough, maybe not even 2.5 bar, but once pressure hits whatever point it takes to escape, it leaks. While a quart in 10 miles is a lot, at 60 miles per hour it indicates a leak of only 1/10 quart per minute.

I would spray the engine down with engine cleaner, hose it off and try to get it as clean as reasonable, wipe wet oily places down with lots of rags as needed. Start the engine and allow it to warm up while parked over some sheets of cardboard and start watching for leaks. If none are evident, it needs to run until the oil cooler opens. If still none are seen, bring the engine speed up to 3000 and watch it. 3000 wont hurt it, but thats around highway speed, possibly when its leaking. It will be loud so some headphones wouldn't hurt. Just keep watching. 1/10 quart a minute should be pretty obvious, its got to be coming from somewhere.

Subject vehicle is not so equipped.

any chance this car had a recent oil filter change?