Prius, overheating P1150. Coolant loss. Replaced Everything

I think spending major money to repair an engine with 240k miles is a bad idea.

 

You could try adding some oil stop leak solution to your oil or head gasket stop leak to the radiator fluid. These solutions seep into the engine seals and cause them to swell, which can help stop leaks and improve cylinder compression in the short term. Such solutions rarely work in the long term however; it might work and you squeeze another 20-30k out of the engine or more before the problem reappears, it might do nothing, or in some cases people have found it to make leaks worse. It's a cheap gamble however for just the cost of a bottle or two. I've personally never used any of these products, just read about them. The right way is of course to replace the appropriate gasket.

If I was to continue to drive it, I'd get a water temperature sensor like a Scanguage so I could monitor the water temperature and drive around with radiator fluid and distilled water in my trunk in case they're needed. Other option is to sell it. I think I'd take ~$2k off bluebook and see what offers you get. You might be surprised what you can fetch for it. The battery and transaxle alone are worth close to $1500.

In any case 240k is a great run for an engine. We're just spoiled in the Prius world where 300k+ is not a rare occurrence.

 

sounds like a great idea.

 

I would definitely do an engine swap rather than trying to replace the head gasket on a car with 240k miles. $395 for an engine is nothing. If you want an engine with fewer miles, try looking for a used engine from Japan. They have high taxes on their old cars and they get rid of them early, sometimes with as little as 20-30k miles.

 

Used JDM engines are definitely the best way to go when swapping foreign motors because they are usually well taken care of with very low miles. The swap should be quite simple and worth the money if you plan on driving the car for a long time. Be wary of super deals on low mileage local engines unless you can hear it running or test the compression on them. Also check inside the valve cover for signs of sludge or buildup indicating a lack of maintenance during use.

 

I would get the $395 engine and put it in. This is what I plan on doing if mine blows. Any idea on what caused a blown head gasket or was it just a freak thing?

 

Do you mind if I ask.. Has your HV Battery been replaced or is it the original?

 

Mine is original 2005 225k miles. I've seen used original Prius batteries out of wrecked lower miles cars for $850 installed which is the way I think I'll go if it goes bad.

Where is the best place to buy these JDM engines?

 

After you reinstalled the thermostat, what was your process to purge air out of the system?
During that process, did you have the cabin heater on, MAX HEAT setting, fastest fan speed?
Did you rev up the engine repeatedly to push air through the system?
Was the cabin heater working satisfactorily at the end of this process, without any sound of air bubbling in the heater core?
Did you check the coolant level in the radiator each morning after performing this process, to top off the engine coolant level? This must be done until the level no longer drops.

 

Bill, do not be afraid to rev the engine. When the gear selector is in P the engine will only rev up to 3,000 RPM or so. If you hear air bubbling around then you must continue the process.

 

If you like the car, drive it til the wheels fall off and buy some more wheels. Seriously, if these cars are maintained they will last a long time. My 05 was pegged out at 300k for who knows how long when the water pump seized up, broke the belt, and overheated the engine. Lack of maintenance from the previous owner. I bought it like that and swapped the motor/trans., the subframe, and the interior from one with 85k on it. Hope it lasts another 300k, it's paid for!

 

Hey Bill, I'm having the same issue. How did you finally figure out it was the head gasket?

I've also had several technicians look at my Prius and tell me my head gasket is perfectly fine.

 

My apologies for necroposting but I wanted to put this back into circulation to try and get the end result if possible. I am having the exact issues mentioned here, replaced all the parts and am now considering doing a head swap

 

2008 with 87k miles...i hear the noise from the engine bay when i park, the heat blows cold...the triangle of death comes on for seconds at a time with the temp overheat symbol... the check engine came on for the p1121 coolant control valve but went off on its own... so the car runs for weeks at a time without issues, then when i add water/antifreeze, and satisfied bled, it starts overheating...should i change the control valve or is this a bad motor?