Replaced HVAC Blower Motor - now a weird noise

I replaced the HVAC blower motor in my 1999 Civic EX after the original went bad. The new unit works fine, but when I turn the fan to the highest position, there is an audible click, like something activating, and then a soft, high-pitched whine. It sounds normal all the way up to the penultimate fan setting.



I can turn the radio on and not hear it, but I want to make sure I didn’t mess something up during my install.



The other weird thing is that when I turn on the rear defogger I also hear a “click”, which I don’t remember hearing before.



Any suggestions?

The clicks are normal. You may have a little bit of bearing wine from the new motor. If so, then replace it or live with it. Alternately, you may have a small air leak that you hear whistling when the airflow is high enough. If so, you may just need to replace some of the foam gasketing where the blower motor installs.

It’s interesting that you mention foam gasketing. There really wasn’t any between the motor’s edge and the hole it goes into when I took off the original. Maybe the aftermarket part isn’t as good a fit.

Thanks for the info… i’ll check it out.