Prius 2010 engine oil in throttle body and chamber

it's normal but can be prevented by adding an oil catch can

 

Virtually all of that oil is coming in through the Positive Crankcase Ventilation (PCV) hose, which returns crankcase vapour to the intake manifold. It's a "U" shaped hose, flared out at the intake manifold end (black chamber you mention):



And guess what: everybody's intake manifold looks like that, a little lake of oil at the bottom. Not to say it's good. And yeah, that's where an Oil Catch Can will help, a lot. It is installed along that hose, between the PCV valve on the crankcase wall, and the intake manifold. Instead of just running along that hose, now crankcase vapour passes through the OCC, and by one method or another, typically some sort of labyrinth, the oil/water/fuel in the crankcase vapour is condensed and retained. They're not 100% effective, some maybe work better than others. You can modified them too by adding steel mesh for example, something to trap the oil droplets better.

You really should remove the intake manifold completely, clean it thoroughly, including the small passages at each intake port for Exhaust Gas Recirculation (EGR). Also, there is a sensor attached near the bottom of the intake manifold, just below the throttle body. This is the Manifold Absolute Pressure (MAP) sensor. It is likely completely oil soaked. I would suggest to clean it with MAF (Mass Air Flow) sensor cleaner if you can get it, though isopropyl alcohol (99%) should be ok in a pinch. The MAP sensor appears a lot more robust than the MAF sensor. The latter is up above, on the snorkel between air filter box and throttle body. This is the MAP sensor location, one 10mm bolt, then it pulls out:



Also, you should look into Exhaust Gas Recirculation (EGR) cleaning. That system takes exhaust gases , runs them through a small radiator (often referred to as the "cooler"), then through an electrically controlled valve, a connector pipe, and into the intake manifold. It's runs along the driver's side of the engine, just beyond your picture edge. The flagged pipe is part of it:



There are excellent videos by @NutzAboutBolts on all of these cleanings and mods, at the top of the 3rd gen Prius maintenance sub-forum. A lot of them connect, for example the spark plug change video has a lot of info on parts removal for access, required for the EGR cleaning. Watch them carefully. I'll post some Repair Manual excerpts too.

And here's some links:

Oil Catch Can, Eliminate that knock! | PriusChat

EGR & Intake Manifold Clean Results | PriusChat

This is what my Moroso 85474 can picked up, in roughly 4000 kms, last winter:



OCC install can be tricky, lots of options. I chose to install mine under the intake manifold, mounted on the main cross beam directly below (you want to mount with some sort of rubber gaskets, since this beam needs to flex). The Moroso can has a tap on it's underside, and I access it at oil changes. But I can appreciate that doesn't work for everyone.

What is common, if you read through the EGR install thread (linked) is to cut the original PCV hose at the middle, and tap into it with hose barbs, run hoses (3/8" inside diameter fuel lines, grade SAE-30R7 is good) to the OCC and then back to the hose. It's destructive of the original hose, but expedient. Here's my plumbing, ready to go in:


(The two cut ends of the original hose are at the ends.)

And install location:



(Note, I drilled 3/8" through holes for bolts, but in hindsight would not recommend it. There are openings in the underside of that beam, and it's possible to push bolts through and turn them from below, but it's very awkward. Sufficient would be pilot holes for some sort of self-tapping screw from above, say #12 size, and put a layer of rubber between the clip angle and the beam, just snug everything.)

(Note: I didn't have rubber gaskets in the connection at this point, but noticed creaking/groaning when jacking up the front thereafter, so reworked it, added some rubber. If you connect to this beam, you want the connect secure but slightly loose, so the beam can flex.)

This is the PCV hose part number, if you want to purchase an extra, say if you remove the OCC and want to restore to stock:

12261-37060

Quick and dirty restore to stock would be to just use the two cut pieces of hose, with a barbed hose splice between them.

These hose barbs are brass, readily easy to find hardware item, for 3/8" hose. Hose clamps are the stainless steel screw type. It's kind of debatable if you even need clamps, the barb splices are very tight, but it doesn't hurt. Depending on your install, a right angle barb might work better. They're not as readily available, but they are out there, typically through hose and fitting specialist supply.

 

wow, nice post mendel!

 

He definitely got his words / post metric a boost.

 

and pics!

 

Maybe we’ll start seeing those from you?

 

maybe. i have an i phone now. well, not really a phone, i don't have cell service, just wifi.

 

Phones make posting pics super easy.

Here’s where I was yesterday:



It was 100 F, which was the only negative.

But the drinks were cold.

 

Pant pant, wheeze wheeze...

 

What are you doing at my house? Lol

 

I didn’t know you lived in Paso Robles?

It was a nice winery and venue.

They even had Charbono there, so I got a couple of bottles.

 

Got my wine ready, might be some unorthodox replies to the forum from this prius owner

 

Just hope you don’t drink enough to be praying to the porcelain god.

Had to help one of the wedding party guests in that condition last night .

 

One hellava wedding. Dare all of us to do that at the next prius meet up

 

No dares needed.

Let’s just say I won’t be holding or supporting anyone during their “reversal of fortune”.

That’s only for family.