Bypass Coolant Storage Tank

New Prius owner from the hot land of Phoenix, AZ.
Recently came across a salvage title 05 Prius with 70k miles that had a front end collision. Drivers side. The car was restored and has been since 2010. Damage was not that bad and I find that insurance companies seem to total out these prius relatively easy. The rest of the car is immaculate. No scratches, dents, dings, anything. The front still needs a little work, and it will now be my project car to drive around town instead of my 2500 Chevy Diesel. (Yes complete opposite world from the prius I know)

Ok so on to my question. I discovered when buying the car that the Coolant storage tank was never replaced as I am sure that it was demolished in the wreck and they didn't want to spend the $ on the over priced thermos. Whoever did the work, just eliminated the tank from the loop. The tank pump is still there and functioning and they drove the car this way the last 2 years. However, this poses a problem.

1. The check engine light is on because of it, as well as the red triangle of death.
2. Closer inspection reveals the temp sensor for the tank is missing. The wire is not plugged into anything. This is causing the CEL code. Cant remember the exact one off the top of my head. But when i clear it, the triangle disappears as well as the CEL and then about 10 secs later returns the same code.

After looking over the flow of water between pumps and valves, I can't find any reason why I need to replace the tank. Rather install a inline T and install the temp sensor into that while I hunt for a good priced tank. $600 for something that just holds hot water and aids in cab heat is something that is not needed in AZ.

Anyone see a reason why this wouldn't work? Keep in mind the car has been functioning this way for 2 years now without the tank.

 

My jaw dropped when I saw how much the tank was. All for a glorified thermos.

I found the sensor online for $5 shipped. Once I get it I will start playing around with it and figure out a way to bypass the tank, or build a much much much cheaper tank that will do the same thing if it still wants to throw a CEL.

 

Patrick, I am guessing you already have some info on this matter. Care to elaborate?

The goal here would be to keep the CEL light off. I see this tank consisting of no more then a bleeder valve, a spot for the temp sensor, an input and an output with my guess is maybe 1 gallon of possibly insulated storage in a closed loop system.

 

Never mind, don't answer that. I just found another post on this issue in detail. I will start there and see what I can come up with now that I know how the computer works and what its looking for.