2012 Plugin Blown head gasket fix

wow! well done!!!

have you ever cleaned the egr circuit?

 

Just to put verbiage to the pictures: bent rod was on cylinder one (passenger side, right side of car)?

Head gasket coating erosion seems to tell the same story.

 

Classic results of hydrolock. It had nothing to do with the water pump. There's no way for the pump to develop that much pressure.

Gen 3 is famous for clogged up EGR systems that let too much liquid pool at in the intake manifold. Eventually, it slurps in too much liquid (which will not compress) into a cylinder, the piston comes up and something has to give since the liquid won't give. Usually it's the head gasket. Sometimes it's a piston or rod. Occasionally it's a combination.

If you don't clean the EGR system, it'll probably happen again pretty soon. There are tons of threads here about the issue.

Great job rebuilding! Just need to do one more thing to prevent having to do it again.

 

Jerry I think the factors mentioned in your second paragraph all contributed, but maybe not directly.

I'd suspect the intake manifold goop ("supplied" by PCV) is slowly introduced to combustion chamber, might accelerate carbon build-up on the EGR system.

The last leg of the EGR is (full circle...) back in the intake manifold: the EGR capillaries (one per port) clog up. The clogging progresses unevenly, with cylinder #1 clogging near-complete ahead of the others. The uneven build up likely due to the EGR gasses being introduced at cylinder #4 end of the intake manifold.

This uneven clogging may delay tripping of codes; the system still detects semi-decent EGR flow.

Meanwhile, due to choked off EGR flow, the engine is running hotter, cylinder #1 in particular. Head gasket starts failing there, coolant starts leaking, eventually you get hydrolock.

 

That is great news about the gasket! How did you see the bent rod? piston head not quite as high at TDC? What was involved with "rebuilding head"?
I know this is an old thread, but I cannot yet start a new thread, so sorry.

I am about to be the owner of a 2012 plug-in with 230K with a blown head gasket. I am going to be rebuilding it (first head gasket job for me). I can look on the Gen 3 forums for a step by step process, with a materials list, but are there any other considerations for the plug in version vs the standard Gen 3?

 

Shouldn’t be any difference in the engine.

clean the EGR system components and intake manifold too; see first 2 links in my signature. On a phone turn it landscape to see signature.

 

Thank you, and I found how to post a thread, here it is: PIP New to me | PriusChat