whitearrow

ok fellas my 2003 es300 is having some screwy heat issues. yesterday there was no warm/hot air blowing on either side floor or dash vents. this morn the drivers side is decently hot and the passenger side is still cold as a wedge. i checked the upper and lower radiator hoses and both are hot,temp gauge shows normal setting between 1/4 to 1/2 at times,doesn't get hotter than 1/2 way on temp gauge,both radiator and recovery tank are full of coolant with no signs of a leak. does my issue sound like a thermostat or air mix servo or something else happening? also, if its air mix servo how many does my 2003 es300 have? i know of the one behind the glove box....any others on drivers side?
thanks,
Big Ed

LeX2K

Normal is not between 1/4 and half normal is the needle is always at half when the engine is fully warmed up (usually slightly below). You may have a bad thermostat, maybe other issues but start there. If you buy anything but OEM you will live to regret it.

HomerJay

+1 on the above.
Also, did you recently service the cooling system? Are both heater hoses hot? If no, you may need to bleed the system of trapped air.

whitearrow

no recent cooling system service has been done. my toy mechanic said bring it to him and we will replace the easiest first being the thermostat then work from there. guess we will see. i really wanted to do this myself but with no clearcut answer guess i'll take it to him.
thanks guys,
Big Ed

Oro

Yes, "normal" is right at 1/2 or a hair over, all the time. So if that's not happening, likely a thermostat. BUT:

That would have nothing to do with the thermostat. That sounds like a blend door issue. And it's pretty easy and quick to repair. You just remove the panel under the glove box and it's along the center console. Remove it, open it, clean it, re-coat it with some dielectric grease and re-install. Don't need to buy a new one - just remove the fine metal debris and dried original grease.

If you temp gauge in fact is getting up to normal and staying there (it should get there pretty quickly - a few miles - and it should stay there on the highway and not drop down), then just focus on the latter. If you swap it and things improve buy not perfect, then clean the blend door actuator, also. If you have any reasonable higher mileage on the car, the blend door actuator is probably acting up because, as they say, "they all do that..."