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Overheating...

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Insight, May 13, 2013.

  1. Insight

    Insight New Member

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    Getting hot outside...over 100f and my used 05 Prius with 79k is giving me the red 'problem' light. I've scanned this forum and gotten lots of info.. When it first overheated the radiator 'boiled over' and decent amount of coolant overflowed. I pulled over, let it cool off, and drove home. I've been reading over this forum for three days now...

    I topped off inverter coolant res, it was starting to approach the low mark, I verified that coolant pump is working. I verified that radiator fans are working. Battery fan is clean and working. How can I test that water pump is working? Oem recalled Water pump was replaced in 2011.

    "Problem" Indicator light refers to 'high coolant temp' meaning radiator coolant or inverter coolant?

    Is this part of the CARB warranty? My 05 civic hybrid's battery went out and it was covered by 10yr/150k warranty here in California.

    I've only had the car 5 months. I put 13,000 worry free winter miles on, but now that it's getting hot out its overheating.
     
    #1 Insight, May 13, 2013
  2. edthefox5

    edthefox5 Senior Member

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    Welcome!

    Try to help here...is there turbulence in the Inverter Coolant tank when car is in READY? If yes that means that pump is working and has good circulation. Many Youtubes on this too btw.

    Look at ICE (internal combustion engine) water pump. Btw, be aware that the reservoir for the ICE coolant can be full but still have low rad level. Take off the top plastic panel and open the cap for the radiator and fill that up. Fill up the reservoir.
    Then with flashlight look at the belt driven water pump on front of engine and look for green specks all over the lower area of the pump the weep hole location. Many many reports of weeping pumps that drain out the coolant and resultant overheat.
    And lastly put car in inspection mode (Utube search: Prius Inspection Mode) and let it run till it heats up and feel both the radiator hoses. They should both be warm reflecting circulation. If one hot and the other cold stuck thermostat.
     
    #2 edthefox5, May 13, 2013
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  3. Insight

    Insight New Member

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    Ok, thx Ed fox , I think I found the culprit... Radiator fans are blowing out, not sucking air in. I couldn't find water pump, will look harder. I did inspection mode and felt hoses, one was warm one was super hot.
     
    #3 Insight, May 13, 2013
  4. RobertK

    RobertK Member

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    The airflow should be front to rear, as it would be with the car moving and the fans off. The fans are counter-rotating, so if the flow from your fans is from back to front it is possible that the fan blades have been switched. Has this car ever been in an accident? Viewed from the driver's seat the left hand fan has five blades, and the right hand fan has seven blades. If these are reversed this would explain your flow.

    The coolant in the Prius should be Toyota SLLC, which is pink in color. If the coolant is any other color I would suspect that whoever worked on the car did not know what they were doing.

    The fans operate on demand based on water temperature but are forced on when the A/C is operating. This might explain why you haven't seen the problem until recently.

    Hope this helps.
     
    #4 RobertK, May 13, 2013
  5. edthefox5

    edthefox5 Senior Member

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    Wow second time I think we have seen this. Should have mentioned it. But since your in the area make sure the AC condenser is clean & bug free. Clogged condenser means no air flow thru the rad. Take that top plastic cover off and hose it out good since you'll have the fans out. Go to Home D and by there can of AC Condenser spray foamy cleaner. Its a blue can. Wet the condenser and then soak it with the cleaner. It does a good job.
     
    #5 edthefox5, May 14, 2013
  6. Insight

    Insight New Member

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    Well, it's definitely reversed fans. At least the one on the passenger side is blowing out and the contour of the blades is facing the wrong direction. I bought it used in January. Got a good deal since I knew it had been in an accident, but had been "professionally repaired". Ha!!!!

    I put 12,000 miles on it in 5 months. Now that it's hot weather, this problem has begun. Lets hope this is it. I'm 90% sure it is.

    This is my fifth hybrid. I had 3 2000 Honda insights, and a Honda civic hybrid, all 5 speed manual trans. I still have an insight, and I lost the other three to total loss accidents. My insight has 235k miles and still gets over 60mpg. My wife really wanted a Prius... I've tried to like it. But, the Hondas are so much cheaper to buy, way cheaper to maintain, and get better gas mileage on the highway. My civic hybrid did 52.2 mpg on my 150 mike round trip daily commute! I've gotten 57 mpg once out of the Prius, when I was in stop n go traffic the entire way. Prius is usually 40mpg:(. I'm switching to 0w-20 and a k&n air filter to boost highway mpg on Prius, any thoughts?
     
    #6 Insight, May 14, 2013
  7. Insight

    Insight New Member

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    Ok, car is running mint again. The radiator cooling fans were installed backwards! Easy , quick fix. I just hope I didn't damage the engine. I put 12,000 miles with the fans backwards , but only overheated a couple times. That's all it takes to melt / degrade the seals and gaskets:(. Oh well... When it would overheat I could hear a high pitched whining sound for about 40 mins after car was turned off. Sounded like a liquid or gas trying to escape through a tiny tiny hole. Came from left of engine, down towards the bottom, possibly coming from trans. Any thoughts on what that could be? Thanks again to all of you here on this great forum!!!
     
    #7 Insight, May 16, 2013
  8. uart

    uart Senior Member

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    I wonder if it was just coolant getting sucked back in from the expansion tank? When you overheat then quite a lot of coolant can get pushed out into the expansion tank, then as it cools down this expelled liquid should get drawn back in as the coolant in the engine cools and contracts.
     
    #8 uart, May 16, 2013
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