Grumbling noise when turning off Heat in car??
 

Hey,

I recently got my radiator replaced, and I thought the noise would go away when the radiator got replaced. I would get a squealing noise every time I turned on my "HEAT" and the two fans would turn on. Any time I turned on Economy mode, I wouldn't get a squealing noise. However when I use "AUTO" or turn the fans up manually, I get an initial squealing noise that goes away. Soon after turning the fans on. I thought this was caused because of my severe coolant leak. But Ive washed out my engine bay and everything and I still get the squealing. In addition to that, I have a GRUMBLING/RUMBLING noise ANY TIME i use "AUTO" to blow heat into my car. I hear it for a second or two and then it goes away. THIS ONLY HAPPENS, when I turn off the "heat". But If i use economy mode, I get no noise. Again I thought this second noise was related to my severe coolant leak where the radiator starts to break up at the top where the plastic is at.

It sounds like its coming from the area in front of my radiator on the driver side, below where I had my old air-box used to sit at...Could this be thermostat? or something else? I had a koyo radiator installed, new upper/lower hoses, and screw-on hose clamps installed.

In conjunction to hearing the grumbling noise, I can almost feel it a little bit. Ive searched and searched and hadn't found anything like the issue I'm having.

Thanks to all

I think when you use Auto mode the system will also kick in the AC for defrost capabilities, economy mode omit AC for better fuel economy.
Maybe it's a loose belt.
That's my understanding of the differences between the modes, and may explain the squealing.

Ok, I just checked out what you said. I listened, in the area where the belts are at. I dont hear ANY squealing coming from that area. It seems like its coming directly where the fans are at, or at least thats my perception of the issue....I cut the HEAT 'on' using 'auto', and I hear the squeal, and I cut the HEAT 'off', using 'auto' and I hear the grumbling/gurgle/rumbling noise

Gurgling is an indicator that there are air bubbles in your coolant system. You'll sometimes hear it when you first start up your car, or after running your heat for a while. It's the bubbles of air moving through the heater core. You'll need to have your coolant topped off to make this go away.

As for the squealing, have you checked the actual blower motor? A whole slew of us have had a similar squealing problem.

I agree with SLCPunk, Is the ac compressor turning on and off when switching from auto to economy. I don't have may Max today or I would check myself. If it does, I still think it's ac related.

Does anyone know if the electric fans are split up one for Coolant and one AC use?

Wait, OP, do you mean you hear a squealing coming from your radiator fans, or the fan inside the car that moves the heat through the ducts?

Edit: What year is your Max? Although, I don't think the heating/cooling system was really changed much from '01 to '02. I could be wrong, though.

Well the gurgling/rumbling noise that I hear is on the side of the engine where the thermostat is at...over in the battery area. I dont hear any gurgling inside the cabin, or coming from the glove box area. The ONLY time I hear it is when I turn my heat OFF using 'auto' If i use economy I get "NO noise"....weird right?



Well I BELIEVE the A/C compressor is turning on and off when switching from auto to economy. All I know is that BOTH of my fans have always spun, I cant really remember if one spins while the other is motionless




Well SLCPunk, I hear squealing coming from the area where my fans would be at OUTSIDE THE CAR, inside the car I dont hear anything. Or if they cut on while my car is warming up and I walk toward the car or something. I have no problems what so ever with air moving through the ducts in my car. Ive got a 2001 Maxima. I can change the direction of the air, from floor to defroster, to the regular vents without any problems at all. Economy at 90 degrees only points air at the floor, the moment I adjust the fan speed it goes into auto mode...which is normal

I just get that squeal when ever The front fans kick on, and then the gurgle when I cut them off...I added more fluid to my car this morning, Not a whole lot but enough to top it off...I check it again now while its cold.

Sounds to me like one of your radiator fans has a bad motor. Might be the result of coolant from your old leak getting into the motor. That will probably have to just be replaced.

As for the grumbling or gurgling, I'm honestly stumped. The only thing I can think is maybe your A/C compressor is kicking on or off. The pressurized/depressurized compressor may or may not make some sounds. I know if I let my car idle and flip the A/C on or off (I have manual controls on my car) the A/C will make some noise until everything gets adjusted.

Ok thanks.! I'm about to upload a few audip clips of the sounds