2012 Prius catastrophic engine failure.

Usually a head gasket failure will show as a vehicle overheating and sometimes with smoke from the exhaust (coolant or oil being burned). If it was violently shaking at startup I would think it was more likely a bad coil pack or spark plug that was fouled.

That being said if the ticking noise was immediate after the change why would you keep driving the car without investigating further. It sounds to me that the top half of the engine was starved for oil or coolant after the head gasket was replaced by either the head gasket wasn’t lined up appropriately blocking the little arteries for oil and coolant to get up there. Other possibilities after the “repair” the oil wasn’t replaced or the air in the coolant lines wasn’t bled.

 

This is why we have courts and juries. You are going to correctly say he did the repair wrong. He's going to correctly say that once you discovered the obvious problem "as soon as you got the car back," you shouldn't have driven 800 miles on it. You are both right.

 

Probably caused by the 800*F rise in temperature when the EGR system is plugged.

Pixel XL ?

 

1. Small Claims Court.
2. Used engine.
3. Read up on EGR cleaning threads and monitor for oil usage on the new engine.

Good Luck.

 

Sounds like EGR is plugged to me. My engine vibrates like mad for years until I cleaned the EGR and the dealer reset the EGR code, they told me that I had a misfire in one of the cyclinders and that the EGR probably caused it.

I cleaned the whole EGR system and I don't have a problem with my engine vibrating or misfiring anymore, the engine had 240k miles on it, here's a pic of part of the EGR system I cleaned

You have similar mileage so I imagined it must be like this too.

 

Good visual.

I just did the second replacement of egr cooler and valve and she’s running strong .

Good to see you posting again.

 

When @danlatu did his head gasket replacment he noticed one piston was slightly lower when at Top Dead Centre. Turned out to be "hydro-lock", basically the cylinder was filling with (uncompressable) coolant, the piston arm bent.

 

I know this is older but this is a VERY common failure mode. Headgasket causes mild hydrolock from water intrusion into the cylinder, probably upon startup. The rod is always the weak link so it bends the rod slightly. Usually you can't see it by eye. The way to check is a compression test. Compression will be significantly lower on the bad cylinder. A leakdown test will not pick up an issue with a bent rod. Once bent it is going to fail, there's no way around it period. Sometimes they last months before failure but they always fail. The only thing the mechanic did wrong was not stopping right there with the head off once he saw one piston was below deck at TDC and suggesting a rebuild while all but the piston and rod were salvageable. Otherwise not his fault. The catch is, a compression test in this case won't tell you much because the gasket it already blown. Now, if it sucked water from driving through a very deep puddle, a compression test would be a sure fire way of knowing there's a bent rod.

As for the EGR, it will cause the engine to run rough and even die if it's at idle and too much exhaust is introduced into the intake charge. You're diluting the intake charge with an inert gas which makes it run rough, all cylinders struggle for complete combustion. Not the same thing, not even close to a bent rod and single cylinder misfire from the lack of compression. Typically a lack of compression shows up the most at idle and depending on how low it is, can completely go away as the dynamic compression comes up with rpm and load. The other thing is the rotating assembly is slightly out of balance with the bent rod which can be a minor contributor to the vibration and can show up at any rpm.

 

Not trying to ask this question in any smirky way, would you buy another gen 3?