New piston design.?

Nope.

Since the egr takeoff is still before catalytic converter, you'll get the same buildup.

But at least there are videos and plenty of experienced folks available to help.

 

^ I should update this. I've heard the new rings and old pistons (or vice versa) are not compatible. Accordingly, it seems likely what happened was "sometime" through 2014 model year, both the rings and pistons were switched (to the new part numbers), at the same time.

 

I believe you, even 4th gen Prius with after cat-EGR still have the same issue. In short, any cooled EGR design need regular maintenance in EGR and intake manifold cleaning. It will still be a problem until Toyota come out with something radicals like how Toyota/Lexus used dual-injection (direct and ports) to eliminate common GDI intake valves problems.

 

oh no...

 

Do you know someone who's torn into a Gen 4 EGR??

 

I have one in my parts bin, but the donor engine had only 5K on it. It looks the same for the cooling fins and surround tank,

 

here are some more good links from youtube carcarenut. worth watching to see what is the root cause of this mess:

Why do Toyota engines consume oil ? And how to prevent it? - YouTube

Here's Why Toyota Engines Consume Oil. Tear down and Repair. - YouTube

 

Only when doing a 4th gen swap. Engine wass claimed by eBay seller to be a 2018 with 35k miles. Was a US-market engine, and by far the cleanest used motor I’ve ever installed.

Looked absolutely brand new inside valve cover when pulled. EGR cooler had very slight carbon dusting inside. Nothing that would have begun to inhibit flow.

I used the 4th gen’s EGR in my swap into a 2011 with 206k miles. Had to restrict the flow into the intake, since the 4th gen’s EGR has a lot more flow and roughly double the surface area inside the cooler.

Everyone else uses the old engine’s EGR when doing a motor swap. I wanted to be difficult.

3G inlet and outlet pipes got cut & welded to fit 4th Gen EGR:


Size comparison - 3rd gen is in my hand:

 

It is extremely easy. If you have skills to pull an engine and replace with the same, you’re golden. Prius have the easiest engine to drop and swap you’ll ever do. No starter, belts, etc. No torque converter or clutch to worry about. Only 1 motor mount. You can pull the engine with intake and exhaust manifolds attached to it, no need to strip before removal.

Then install flexplate, intake, exhaust, engine mount off you old motor and drop it back into the car. The only hard part is some tweaking of the EGR brackets and re-routing the coolant lines since things are in new spots.

I have done 3 now. My own car and two others. Being a former Toyota Master tech, I tend to do some sidework on Japanese vehicles. Did two for guys in the Memphis area. Charged $3,600 including price of the engine. All three run flawlessly.

 

this thread should be pinned