Head gasket

i can't see how the passenger side heat could be related, but exhaust in the cabin should be taken care of immediately.
the heat is either hot or it isn't. if you're getting warm air to the driver, it should be a stuck vent door or bad servo motor.
either way, you're going to have to fix the head gasket, replace the engine with salvage, or move on.

 

Heater core probably plugged and everything else that has coolant in it..... I have the same car but I cleaned the EGR system over 40,000 miles ago...... 240,000 + now and never low on fluid..... but you never know..could blow today.... you really need a parts car if you plan on keeping one of these. The traction battery will probably go in 30,000..... these cars really aren't that great unless you plan on trading every few years or don't put lot's of miles on them.

 

So is it just the Prius V bit seems to be not great or is it the third generation engine in particular.
Makes me a bit nervous because I have some friends that have a 2014 v that they bought with about 40,000 miles on it. Car now has 160k on it so far it runs fantastic.
is there some preventative measure that they could take regarding the EGR tube is that what causes the blown head gasket issues?

I personally have a second generation car with 311,000 on it.. and it runs flawlessly gives me 45 to 50 MPG

Posted via the PriusChat mobile app.

 

They need to clean the entire EGR System Valve and Cooler ASAP....... it plugs up and can cause a head gasket problem besides numerous check engine codes. And remove and clean the plastic intake manifold......and I have installed a catch can.....
And I think the 10,000 miles oil change is way to long...... my v has 247,000

 

I see the switchover of pistons and rings (in an effort to reduce oil consumption) happened in model year 2015 with the Prius v:

I'd second that: clean everything between the connection at the exhaust manifold and intake manifold, AND the complete intake manifold, paying special attention to the EGR tributaries (one per port). And clean the intake ports while you're there.

Watch @NutzAboutBolts videos, linked in 3rd gen maintenance forum, a thread pinned at the top, he covers all that.

A few "coolant" tips:

When taking off the throttle body, it is not necessary to disconnect it's coolant lines.

When taking off the EGR cooler, it is necessary to disconnect it's coolant lines, but if prior you drain two quarts from the radiator drain spigot, the EGR will be high and dry. When done pour the fluid back into the reservoir. Also, take care when lifting out the EGR cooler, there'll be maybe 1/2 cup of coolant trapped at the back/lower corner. Just add that to your previous drain.