check hybrid system

Hello all

I have read a ton of threads about this and still need some help

Last night the check hybrid system light came on on my 2010 prius.

3 weeks ago we had to replace the gas engine and ac compressor. it blew a head gasket and the motor at 220,000 miles. threw a rod that hit the ac compressor. needless to say i am really deep into repairing this prius and need some real help.

Last week I had to replace the 12v battery

I had 3 codes set since getting the engine replaced

1 - catalytic converter code - the day we got it back from the shop 3 weeks ago it set the catalytic converter code. we checked it but the check engine light reset after a day or so

2 - an upstream o2 sensor error that cleared after a few days. The o2 sensor came in today. I will likely replace this while waiting for help with the other issues.

3 - it also set a Mass air flow sensor code yesterday again the check engine light reset after a bit of driving

i noticed yesterday the engine was making a rasping sound at 70 miles an hour and it was having trouble maintaining that speed. and think it is the catalytic converter being stopped up.

last night when the check hybrid system came up i was able to restart the car 4 times to clear it and drive the 7 miles home.

now the car starts very rough and will only move a few feet before shutting off. it will restart though.I checked the invertor coolant reservoir and can see the level change slightly as the engine starts and shuts down. I cant determine if there is a flow while running it doesn't seem to have any turbulence.checked the 12v Battery it is strong as 12.8v with engine off and after having the accessories on for a few minutes ( ac radio)

I don't have a code reader and can not get it to the auto parts store i usually have check the codes.

any one have any ideas that i can try to do a better check for the invertor cooler pump?
i read it could be the sensor for the 12v battery how can i check this as well?

Any other ideas on things i can check out that might be the answer?