High pitch squeal from passenger side rear. Video included

[Zoso]

2015 Passat TDI SEL. ~9600 miles.

The other day, when it was particularly cold (~0F), I heard a nasty squeal that seemed to come from the passenger side rear of the car. I took a video:

https://www.youtube.com/watch?v=eq7YkBYK234&feature=youtu.be

Eventually the noise faded away and I haven't heard it since. Any ideas what this noise could be? I'm bringing it in for the 10K service so this would be a good time to address any issues!

Thanks!

 

[Herkguy]

Only two pumps near there are fuel tank and DEF. I wonder if the DEF was frozen and pump was running, then when DEF heater warmed fluid, it quieted down.

Show the dealer your video though when you go in for service.

I live in MN and have never had that sound even on coldest days.

 

[psd1]

My guess is DEF pump. If it happens again open the trunk and DEF hatch and see if you can pinpoint the noise.

 

[tdiatlast]

How much fuel in the car? Wish you had taken the audio clip from inside as well. Under certain conditions, the in-tank pump can make a similar sound, in my experience. It isn't failing, just finding a certain frequency that is magnified by specific fuel level.

 

[psd1]

How much fuel in the car? Wish you had taken the audio clip from inside as well. Under certain conditions, the in-tank pump can make a similar sound, in my experience. It isn't failing, just finding a certain frequency that is magnified by specific fuel level.

Interesting thought, with 55 fuel ups I have run my car from completely full to running on fumes and have never heard the sound posted in the clip.

 

[Zoso]

How much fuel in the car? Wish you had taken the audio clip from inside as well. Under certain conditions, the in-tank pump can make a similar sound, in my experience. It isn't failing, just finding a certain frequency that is magnified by specific fuel level.

I don't recall, but I typically don't let it run low enough for the low fuel light to come on, so all I can say definitely is that it wasn't critically low.


Herkguy's theory about the DEF freezing is interesting and seems believable to me. I just read that (32.5%) DEF freezes at 12F and I'm sure the outside temperature was under 0F throughout that night. The only odd thing is that if the DEF was frozen, you'd think this would happen all the time to people in cold climates and people would recognize the sound.

Everything about diesel engines is new to me!

 

[tdiatlast]

Zoso: All AdBlue equipped cars have a heater built into the DEF system. Search a bit and you'll see more than a few failures of the heater/pump system, which, AFAIK, are all combined in one inseparable unit.
IF your problem is the AdBlue pump, it will be the first one reported here that failed with a loud squeal.

 

[dogger37]

fuel tank is directly under the rear passenger seat. If you push back and up on the seat cushion you can actually see the top of the tank.

 

[jrm]

Post up some cold start EA288 videos!

 

[Zoso]

My local dealer says they showed the video to their master techs and also to someone in vw America and were told that the sound is normal and is a flap in the exhaust system. The noise sounds mechanical to me but I was told it was exhaust gasses going around the flap and it went away when the car warmed up enough and the flap opened.

 

[tdiatlast]

Zoso: TOTAL BS. Find another dealer.

 

[jimbo1mcm]

BS agreed. Amazing incompetence and uncaring.

 

[Zoso]

What bugs me more is that the tires weren't rotated. I'm not sure what is exactly part of the 10k service but all they did was change oil and filter and top off adblue. Car wasn't washed or vacuumed either. Was told the doors were getting frozen closed after the washings.

 

[tdiatlast]

Zoso: Your car is screaming at you and you're worried about your tires rotated? It ALL adds up to distrust of your dealership.
Find a trusted mechanic in your area.
(Of course, with all the snow you've got, your issues even more inconvenient...sorry about that!)

 

[mattinak]

My 2015 Jetta TDI is making the EXACT noise as in Zoso's video clip. It is inconsistent --sometimes I hear it, sometimes I don't. It is only heard when stopped and idling, or when driving at low speed. (it may be doing it when driving normally, but if so, you can not hear it above highway noise). Sound is definitely coming from passenger side, underneath, towards the rear; sound is not more noticeable from open trunk. From inside the car, it sounds just like the whistling noise you get from rubbing a wet finger around the rim of a crystal glass. I am in a cold weather climate, if that makes a difference.

I see there a lot of guesses in here... is there any consensus as to what is actually causing this noise?

 

[jimbo1mcm]

What bugs me more is that the tires weren't rotated. I'm not sure what is exactly part of the 10k service but all they did was change oil and filter and top off adblue. Car wasn't washed or vacuumed either. Was told the doors were getting frozen closed after the washings.

Sure they changed the filter? It's a PITA. So easy to just say they did it.

 

[ArtK65]

I too have heard the same sound from my 2015 Passat 6MT, 15K miles. It didn't sound nearly as loud as what I hear on the video. I did add a gallon of adblue, and it seemed to go away, but that also coincided with filling up the fuel tank. I have heard it again with about 3/8 of a tank of fuel.It was definitely not that cold out, maybe in the 30's.

 

[c-wagen]

I have heard a similar noise (similar pitch, but not as loud, more like a humming) when in cold weather (30 to 50s) if the diesel tank is below 1/4. I'll check with warm weather this summer. I would say is the diesel tank fuel pump, but I don't know if is going to fail or not (more than 2 years hearing the noise). Yours is really loud. Mine's a 2012 Passat TDI SEL

BTW, does anybody know if there is a pressure gauge metering pressure at LPFP intake, so engine can shut off if fuel is pressure is low/ fuel is not flowing (empty tank, or fuel tank pump failure)

 

[PaulB]

Fuel pump is my guess. I started getting a ringing noise when accelerating, coming from the right rear. Pull up the rear seat and it gets really loud; that is how you can tell. I had mine replaced but I can still sometimes hear the replacement pump squealing. I care less though; I can deal with a little noise now and then, as long as I don't get stranded.

 

[brian_e]

From the video I definitely thought it was the fuel pump. As other suggested you can check from the inside to confirm the fuel pump or, perhaps, the DEF pump as others suggested.

No way in hell is it an exhaust flapper or that this is even a normal noise...

 

[Rico567]

Last week, I changed my fuel filter and then ran the lift pump with VCDS to make sure the lines were full of fuel. The sound audible from inside the cabin was not unlike the one in the video, but of course it wasn't loud at all, could only be heard because the car wasn't running and there was no other background noise. But a high-pitched whine, yeah.

 

[Itzed]

My 2015 fuel pump squeals also. I'm m not too worried about it. My 1980 Scirroco pump sounded the same way for 300K miles.

 

[Funguy]

Count me in, I have the same noise. It stops a few seconds after shutting off the engine. Thankful that I can't hear it at speed as that would drive me up the wall

 

[VeeDubTDI]

Fuel pump. DEF pump is much lower pitched. The fuel pumps have a tendency to get louder as the temperature drops and viscosity increases.

 

[Funguy]

Fuel pump. DEF pump is much lower pitched. The fuel pumps have a tendency to get louder as the temperature drops and viscosity increases.

Holy cow it's 98 degrees here! Can't wait to hear it in January.

 

[jrm]

also loud when tank is near empty- almost loud as the 90's chevy trucks. eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

 

[VeeDubTDI]

also loud when tank is near empty- almost loud as the 90's chevy trucks. eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

Yep. Ours got particularly loud one time when I ran the tank low, but it was only that one time early in its life. At first, I was a bit concerned, but it went away when I filled it up. I believe that was on a cross-country road trip a few summers ago, but I don't remember exactly.

 

[Funguy]

I have a long trip coming up. I will be sure to have some CD's that will drown out the squeal should it become too loud.

 

[dbias]

Fuel pump. DEF pump is much lower pitched. The fuel pumps have a tendency to get louder as the temperature drops and viscosity increases.

That's is a lot louder than the fuel pump on my 2015 but the exact same sound, pitch.
Took it in right before 36k and they replaced it and the right front swaybar link.
Cannot hear it at all now.
On the old pump the noise was always louder at a quarter tank or less

 

[luther]

Same noise here when the fuel tank level drops close to the red line.
Not very loud, but you can still hear it. 2015 Passat TDI SE 2.0L
Noise seems to go away after filling the tank.