The heat in my 2008 Prius does not get warm for 25 minutes when starting to drive the car. The thermostat has been changed and is working fine. Any suggestions on how to remedy the situation. The AC works fine.
So you have no heat.? Open rad cap on morning water should be standing at top of filler neck very top ??? What ya got?? Make it so . You'll have heat on like 9 min . When you don't again open cap ! Find out why it's not at top .
Checked under radiator cap before started car this morning….and the water was up to the top of the neck. But same situation — blower motor blowing but heat was barely warm.
Just because it's new, doesn't necessarily mean it's working properly. FWIW; if you trace-out the coolant pathway diagram - you'll find that a thermostat stuck in the open position would just take a lot longer to get heat into the cabin. Was the old one stuck in the open position? Check the two heater hoses going through the firewall, they should both be warm. Also check water pump operations. If the thermostat is closed, the upper radiator hose, coming from the thermostat housing should be cold - NOT warm. A warm hose would indicate that the thermostat is open - which is what @ChapmanF was looking for as an answer. Good Luck.....
This may sound like a dumb question, but is the heat turned up all the way? We had someone on here a month ago in Seattle area that hit freezing temperatures and person posting had their heater set at lowest setting of 65 degrees. Never heard from again after I pointed that out. Lol... Also when was last time you replaced cabin air filter? Also if you buy an OBD2 reader like this one: http://www.ebay.com/itm/265484403768 You can use a phone app, like Car Scanner (Elm) to monitor engine coolant temperature which will help us with diagnosis.
My husband checked the old thermostat and the new one and they both opened and closed while doing a test in boiling water….He then put the new one in the engine…and it worked just like the old one….barely any heat…he will do the diagnostics that you have described to see if this new one gets stuck open. And we have the heat set on the highest setting 84degrees.. And will check the cabin air filter…I had bought one but cannot remember if we replaced old one. @ChapmanF @BiomedO1 @Tombukt2 Also, I do not know how to use this forum…am I supposed to list all of your names in a reply?
The highest setting is hi. All Ieant yo know en you walk out to car in am open rad cap is water at top of neck ????
What is the outside temp when you go out in the morning and you're expecting heat and radiator is at top of neck.
Gen2 Prius coolant flow through the heater is complex because of an extra water pump, control valve and storage tank in addition to the normal engine water pump and thermostat. 3 way Water valve Possible issues are a clogged heater core, air in the coolant system, a bad air blend door actuator, bad heater water pump, bad water 3 way valve or coolant leaks. Because of the complexity Toyota has special scanner based tests. Many of the issues create Toyota specific codes that auto supply scanners can not read. If the coolant temperature is 180f or higher and the engine is not overheating, use of Toyota Techstream active tests or another advanced scanner is recommended. Car Scanner is not capable of the active (bidirectional) tests. Even bleeding air out of the cooling system is best accomplished with a good scanner. Sometimes its better to let a hybrid experienced shop do a diagnosis.
