Hello, i just got a 2010 Prius with 208,000 miles about a week ago. Before I got the car they put a new coolant temperature sensor in since an engine light was coming up for it and it went away and everything was fine. A few days ago the engine light came on for PO177- Engine Coolant Temperature (ECT) Sensor Circuit Low Output Problem. The cars heat doesn’t work and only cold air comes out. I also noticed the coolant was low even thought they filled it up right before I got it. The High coolant temperature warning light comes up every time I accelerate a little hard or drive over 60mph and doesn’t go away until I let off the gas and let the car cruise for a while. I filled up the coolant yesterday and i didn’t see anything leaking but today it is back down again. Also I have an engine light for misfire on 2 &4 and right before I got the car they put new spark plugs in. Any advice on what I should do or what the problem could be? Thanks.
You were tricked into buying a car with a blown head gasket. I’m sorry this happened to you. Go back to the seller.
if it was me I would give them the opportunity to make it right. If not, I punch them in the mouth and walk away with some satisfaction.
If you keep the car, after doing the head gasket (assume that's the problem, a fairly safe bet), immediately clean the Exhaust Gas Recirculation circuit (all components), and the intake manifold (pay special attention to the EGR passages, one per port). And install an oil catch can.
