Fan noise

rmilchman

Well-known member
Joined
Jun 9, 2014
Location
Robbinsville, NJ
TDI
2014 Passat TDI SEL
I think my auxiliary fan is going bad, but looking for confirmation or another suggestion. When the fans are running I can feel a vibration through the car. When running at full speed and the flaps also open there is a lot of vibration and the noise generated is louder then the engine itself. Here's a video when they are running at full speed.

https://youtu.be/16XzUYeiGzA

If they are running at full speed and I shut off the car, they immediate slow and the noise is softer.
 

joshferrer

Well-known member
Joined
Jun 6, 2018
Location
Ontario, CA
TDI
2014 VW Passat TDI SEL (CKRA)
I think my auxiliary fan is going bad, but looking for confirmation or another suggestion. When the fans are running I can feel a vibration through the car. When running at full speed and the flaps also open there is a lot of vibration and the noise generated is louder then the engine itself. Here's a video when they are running at full speed.

https://youtu.be/16XzUYeiGzA

If they are running at full speed and I shut off the car, they immediate slow and the noise is softer.

Have you checked the ac lines right next to the frame? I had an issue like this where I thought it was a fan. I was able to track it down to one of the lines that was just close enough to rattle against the frame like crazy making that sound. I moved it just a little further out and no issues after that.

I also did end up replacing a fan after that line fix but that was more because that specific fan was crooked making it wobble when spinning and creating more vibration than I wanted. It wasn’t noisy like this though. That helped that issue too.


-2014 Passat TDI SEL
 

rmilchman

Well-known member
Joined
Jun 9, 2014
Location
Robbinsville, NJ
TDI
2014 Passat TDI SEL
Do you recall where the AC line was? On the top frame in the area of the fuel filter or on the bottom somewhere? I went out and tried to move some of the lines up top and make sure the rubber fittings where in contact with the frame. Then took it for a ride, I guess I didn't get it hot enough for the fans to kick in full speed. I'll try a longer drive tomorrow after work.
 

rmilchman

Well-known member
Joined
Jun 9, 2014
Location
Robbinsville, NJ
TDI
2014 Passat TDI SEL
Couldn/t find any AC lines rattling. I tried using a screwdriver and touching different lines while I heard the rattling. Cooling line on left side of radiator barely vibrated, cooling line on right side the screw drive would jump around.

Any suggestions?
 
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