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Heater on ES300

The heater on my '93 ES300 seems a little weak (although I just bought the car a couple of months ago and didn't use the heat until the last few weeks). I notice that when I first turn it on, I get a burst of heat, but then the air seems to cool down. It never gets cold, but it doesn't seem to be as hot as it should be. The recirculated air, however, is plenty warm. I know it isn't coolant-related since I just had the radiator cleaned and flushed out a month or so ago. Any ideas?

Reply to
Donuts
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Several possibilities, assuming you have automatic climate control: One of the blend doors is not working correctly; The interior temp sensor is not working properly; The temperature control is not working properly; The heater control valve is not working properly; The heater core is clogged

Reply to
Ray O

Thanks. I don't think it's the sensor, since I have the same problem when I use the heater in manual mode. Is there any way I can check the heater core myself, or is that something best left to the mechanic?

Reply to
Donuts

The interior temperature sensor controls temperature whether it is in auto or manual mode.

You can check the heater core by checking to see if warm water is coming out of the heater hose on the firewall. While you're looking there, look for the heater control valve to move while someone moves the temp up and down.

Re-reading your original post, if the recirculated air seems to be warm enough but the fresh air is not, then I would suspect that a blend door is not functioning properly.

Diagnosis requires someone with a factory repair manual, like the dealership.

Good luck!

Reply to
Ray O

Thanks again. I've heard of people cleaning out the interior sensor themselves and that it's located on the driver's side sort of near the fuse panel and the vents. Any idea where it might be?

Reply to
Donuts

The interior sensor will behind a postage stamp-sized grille somewhere on the dash, usually in a low and unobtrusive location.

Reply to
Ray O

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