Weird stuff with my heating system. car has about 3200miles.

When you turn the heat on, it'll randomly raise the idle to around 1.5Krpm. I forgot but I think this only happens on the window defrost setting.

The heating for the feet does NOT warm up at all. I drove the car for 2 hours, with the heat set to just the feet and at the 3rd setting. My feet never once got warm. Feels like it's just blowing cold air.

Also - heat on and set to the window defrost setting - rolling at around 5mph and in 2nd gear it makes a shuddering noise from the passenger side. Kinda like you're sucking air and water through a straw. I only hear this when I have it on the window defrost setting. I have not noticed it at any other setting.

Is this normal?

 

Yes, it's normal. The defrost is operated with the A/C, and yes your idle raises with the A/C on.

Darin

 

ok, so the idling up is normal, what about the other stuff? Why is the defrost operated by the A/C anyways?

 

A/c helps window defogging. In my WRX I have the option to turn off the A/c tho. My RSX did not have the ability to be turned off (w/o modification).

 

Most manufacturs started defrosting thru the A/C years ago, it's a more effective way to defrost without adding more moisture to the window.

The other stuff, well, you're on your own on that.

 

The A/C is operated under defrost mode because it de-humidifies the air making it easier to defrost the windows. You engine idle will automatically increase to compensate for the heavy load the A/C uses. You will notice that your car runs like shi t with the A/C on then with it off. It robs power.