random cyl misfire

Add an oil catch can

 

You’ve yet to clean the Exhaust Gas Recirculation valve/cooler?

more info:

Bad Flywheel | PriusChat

 

where did you gas up?

 

When and if you do the head gasket, everything else will be good. Often the coolant loss is very minimal at first. Typically the rattle will clear within a minute and run fine after.

Prius Knock Knock Who's There?
Its me, Cylinder 1

Stage 1
Spark Plug and Coil Change
Clean EGR
Monitor Coolant
Try Head GasketSealant

Stage 2
Order a Motor from Japan
Arrange Killer Install Deal

Stage 3
Question Motor from Japan

Stage 4
Decide to DIY Change the Head Gasket, Change Gasket

Stage 5
Reconsider Motor if yours might have a Bent Rod

 

Unless the bent rod was accompanied by irreparable damage to the block itself, I would simply replace the rod assembly (P/N 13201-39185, $68-$98).

Unbolt the AC compressor from the crankcase (3 bolts) and hang it out of the way. Get directly underneath the engine and unbolt the crankcase (with oil pan in place) from both the engine block (11 bolts) and the transaxle housing (6 bolts), and pry it off to access all the connecting rods. The only specialized equipment needed will be at this stage—a 12-point 10 mm socket ($5) to remove the rod bearing caps.

To transfer the old piston to the new rod, just heat it in water over a stove to 80-90 °C until the pin can be pushed out with a wooden dowel and hammer. Heat again, push the pin in through the new rod, and put the retaining rings back. While reinstalling the piston assembly, use a piston ring compressor rented from an auto parts store ($0).

 

Depending on previous oil consumption it might be worthwhile to replace all 4 pistons and rings, with the 2015 model year part numbers. AFAIK you have to do both; revised rings don’t fit the old pistons.

So unbolting the mid-seam of the block and it’s connection to the transaxle, you access the full length of the crankshaft. And the top half of the block is still stable? You’ve got the head off too?

 

Its pull engine time in that scenario.

 

Before you start the heart-hung transplant, double check the fuel.
The Heet DEFINATELY won't hurt.

LOTA gas stories in the news in the last two weeks.

Usually a rod gets bent AFTER the the lubrication and coolant systems start swapping fluids and the engine makes a milkshake in the oil sump.
My finely honed Spidey senses are telling me that this might not be the G3 Death Rattle....even though the fact that the misfire is still present even after the plugs/coil packs were changed is somewhat troubling.

Keep us....posted.

Good Luck!

 

With the head and the crankcase off, the remainder of the block was still stable. Working in my apartment parking lot with minimal equipment I didn't have the opportunity to pull the entire engine, so I removed only the minimum necessary.