After egr cleaning codes remain didnt fix shaking/stall

Hi all. New to prius chat but cant thank all of you for the help you have given to make this website invaluable. I purchased my 2013 prius gen 3 last christmas from friends that had it serviced at Toyota dealer from day 1. It had been running great and I checked for codes with bluetooth adapter and torque and Dr Prius and hybrid assistant. Also got techstream and usb adapter. No codes until this problem.
Driving slow after a downhill run it started shaking itself violently and died at 130085 miles. After tow home found codes
P0102 maf low input
P0113 intake air temp high input
P3190 poor engine power
P3191 engine no start
detail codes 526 612

Cooler and manifold plugged up good but not completely. I could blow air through the cooler. So I cleaned the egr, cooler, pipe and intake maniforld, especially the little egr ports. Put it back together. Installed new plugs and MAF. When I try to start it now it spins the engine smoothly for 2 seconds, rpms increase and runs smoothly for another 2 seconds then it start shaking itself to death again like before. I found evidence of rat presence so I inspected the wire but didnt find any that were damaged. I triple checked all my work and didnt find any reason for the shaking. So I got a borescope and inspected the cylinders for coolant. Didnt find any wet or super clean cylinder heads. All the pistons had fairly substantial carbon buildup, probably from the egr mess. Both batteries are charged. I need suggestions on how to find the problem and/or verify if its the head gasket. Not sure what to look for. Thanks in advance.

 

When I first got the car I needed to add a small amount of coolant, maybe 1/2 quart. I thought that was normal for other 10 year old cars so never thought about it. I am new to techstream but have seen freeze frame values, will try again. Already cleared codes and it just repeats the problem and codes. What is the IAT? I keep thinking it needs gas but the gauge might be tricking me. Will add 5 gallons and try again. Also rat tracks were scattered, seems there is a nest above the oil filter cover. Havent checked for wires down there.

 

Wasnt sure where they belonged but probably from a P0AA6 which disappeared when I disconnected the HV battery charger. Makes sense since it is an electricity path to the grid. The other codes keep repeating.

There were a couple droppings along the valve cover next to sparkplug wires

First thing I checked but dont see any frayed or damaged wires. New MAF was a cheapie. Will try again with original. I put NAPA plugs in, should I change them back to the plugs I pulled? They looked brand new and consistently all same tan coloring.

As stated part of the MAF but just checking, there is also the MAP below.

Ah yes the pcv. I actually got up in the middle of the night to see if I was had reconnected it. Yes it is connected. Need to add my OCC if I can decide where to locate it.

 

This is where Im at now. But cant figure out how to connect to apply pressure. The reservoir has a twist on cap with o-ring seals below the level of the overflow tube. Need to remove cap to pressurize. I have 2 air sources for the task. Only 15 psi needed. But also expected to see steam cleaned piston heads which were all carbonized and no wetness observed. Will keep trying. Autozone rented me the borescope for 3 months so I have time. Followed this guy at The Car Care Nut:

 

Today when I went to check wiring I had put car in accessory mode (push start button twice, no brake) to play music while I worke. The egr valve got very warm to the touch. Is this normal?

Yes it does go through. Normally (other ice cars) it would be the same as the coolant overflow. I can blow air through it but it is blocked by the o-rings. Thinking of getting a new cap and drill a hole through to by pass the o-rings. First I will try the rubber glove with rubber band around neck.

Welcome to the OCD club

 

Sounds like a plan. Was an electrician before, have the t-pins etc. Did replace the MAF and it still rough. Engine wont start as pushing the gas peddle causes the engine to stall.The head gasket is just because I too am OCD. The egr cooler was very blocked even if i could blow through it. In cleaning I took 3 days of soaking in oxi-clean and reaming out the channels. Intake manifold may have been completely blocked. I read somewhere that a blocked egr operation could cause blown head gaskets. Not seeing any evidence of bad gasket so I postpone further testing. Thanks

 

Finally got to checking wiring and found that eg2 circuit for the maf sub system had a resisitance to ground of 20 ohms, specs say less than 1 ohm and manual says to replace ecm (toyota service manual page 2221). Do you all agree? If so whats the best way to replace ecm? Will a tested used one be ok or should I go with the Toyota refurbished unit? Or should I check something else. I think I need to do the same test but before and after unplugging ecm connector to be sure the resistance is in the ecm.

 

Wiring was checked according to service manual, just want to verify ecm bad.