I have a similar problem. The car runs fine but will overheat within ten minutes of driving, then back to normal, heating will blow cold air during the overheat then back to normal for a while. I got a P0117 code pointing to a faulty coolant temperature sensor. I did some reading and replaced the thermostat. When I tried to replace the coolant temperature sensor I got a new code P0118, indicating that this time the sensor was getting too much voltage. This resulted in my radiator fan running like mad and the engine never heating up. I have the old one back in and now do not know what to do.

 

Okay so same exact problems ive blew one engine head due to this took to a mechanic new head/ gasket yada yada. About a year later with small over heat problems, I would just release some pressure and itd purge out would have to do this maybe once a week. Then one day late for work it went straight from cold to hot then coolant everywhere. I ended up saving this head but while replacing the head gasket I broke a cam very very easily I guess from two full over heats. So I replaced the cames head gasket noticed the last mechanic didn't replace any of my cooling components thermo housing water pump or radiator so I replaced the water pump and radiator along with resivor and been threw 4 caps now I tee valved the heater core which helped alot in bleeding the air out but I still cannot get it to stop over heating when I'm driving and not idle I even put a hose to the tee vavle and took all the hoses off to make sure they were all flowing threw and still cannot get it to stop!!! I'm thinking my next option may be driving it into a tree??? Idk if anyone's had any luck in that method but I'm about to go crazy!!!

 

On some other brand cars it was found that aftermarket (non-OE) replacement pumps had poorly-designed impellers, the part that actually moves the water. This caused overheating, and when a new OE pump was installed the problem went away.

In certain areas of your car it pays to pay the dealer for the OE part. Cooling items is -- in my humble opinion -- one of those.

 

Hey xeroguitar, did you ever get this sorted? I have a young girl, friend of the family who is having the exact same issue. I have done everything that you did… New thermostat, radiator, new cap. Even temperature sensor. And I cannot get the thing to not heat up under load. You can let it sit there and idle for days and it will be fine. But as soon as you start to get on the throttle, the temperature goes to the moon. Just wondering if you ever got this sorted? Thank you.

 

I know this is a very old thread, but I have a young friend who has a 2009 that is doing exactly exactly all this! It will sit an idle for days and will not overheat. Will start to blow hot air But once you start driving it, the temperature gauge goes to the moon! As soon as you back off throttle a little bit, it will come back down. And then when you sit an idle again, it will no longer blow hot air. Everything has been done. radiator, thermostat, temperature sensor, cap. But not water pump. I figure if it will sit an idle and not overheat, and it is circulating. Which it is, because once it warms up, you can see the cool drop in the reservoir the thermostat is opening and fluid is circulating.

So I am at a total loss!! This is so backwards to the way things should be.

SO DID ANYONE HERE GET A RESOLUTION? TIA