Air trapped in ICE coolant system

I have a 2010 Prius. I recently replaced the head gasket in it after having the dreaded knocking on startup and cylinder 1 misfire codes.

However I fixed those issues I now am having problems in what I’m assuming is air still trapped in my coolant system. I have replaced the thermostat and attempted several times to fire up in manintance mode and bleed air out of the system falling several recommendations I have seen on here and YouTube. But I still get the coolant light flashing for short periods and going back out and on longer runs end up with the coolant reservoir steaming and letting coolant out. Twice now I have blown the small line feeding back to the tank at the plastic y connection. What am I missing here guys. I did have one code for the water temp sensor taking to long to reach temp.

 

Also another question if I can feel the coolant flowing in the lines and air bubbles. And see coolant moving in the tank. My water pump should be good or is there a chance of it being weak and not working as well as it should. Sorry just been stuck on this issue and with fuel prices climbing I need this car running.

 

I did tear the egr apart and fully cleaned all the components of it. But I did not have the head machined.

 

Yes it runs great around town on stop and go traffic. But on longer Highway runs it ends up over pressure the tank and blows my coolant out. But the light never comes on and stays on very long. I’m considering trying a airlift pump to refill my coolant and see if I can get it that way.

 

No was hoping it was just a matter of air still in the system but may have to consider that option to.

 

If I pulled a vacuum with a airlift would I be able to verify it’s holding by making sure it held vacuum on the system before filling.

 

It stays level until I drive on the highway and then the light comes off and on sporadically ie bigger hills. Then goes right back out. I haven’t done a leak down test and didn’t machine the heads but never had this issue before the head gasket repair.

Also had good heat after last attempt to bleed system

 

So today I got a Bluetooth adapter and downloaded torque app. I now think my water pump is bad. It comes up to and holds at 221 with fans on and cap off. Then starts to overflow as coolant heats up. Is there anyway to try to cycle it from the app I don’t have a code for water pump.

 

No I haven’t tried that. I replaced the thermostat cause that was my first thought too that it wasn’t opening. Unfortunately it’s built into the housing and I can’t take it out and put it together without it on there.

 

Ok thanks I may try that this evening I rented a coolant gas tester to check if I’m getting exhaust in my coolant. So I’ll let ya know what I figure out there. Also quick question I’m getting a code for my engine coolant temp sensor would that possibly be telling my water pump not to turn on or run hard enough if it’s bad. I’m gonna buy one and change it out and might pull the thermostat back out while I’m tearing back into it.

 

Well unfortunately I’m fairly certain on my coolant exhaust test I ran that my head didn’t seal up right. Guess good news is I’m already more familiar with what it takes to get the job done. My fatal mistake was I didn’t have the head machined and this time I will for sure. Probably will replace the water pump too while I’m there since I’m getting up there in miles on it. I cleaned the egr system last time I had it all apart.