Thread: Noise like blower motor bering

I have a noise like a blower motor bearing needing lube hum. But its not the blower motor. I have replaced the motor and also listen to the blower motor not installed and it is quiet. The noise is coming from behind the dash but I can not tell from where exactly. If I turn the blower motor of no noise. If I put it on first setting hum or wine noise. I can't figure this out. I have tighten the 3 screws holding the motor in and also put my hand on the motor while it is turned on to check for any vibration or change in the noise and there is none. What could be causing this. Is there any thing else on or vacuum motor engaged when you turn the blower motor on? Any ideas?

Could be a vac leak at the HVAC headunit causing the strange noise. Maybe time to check for broken vac lines to it and be sure it's all connected tightly. Other than that it could be internal to the unit. Without hearing it, it's kinda hard to tell but I've heard a vac leak make a squealing noise before on other cars.