Hi 👋 

 

I just got this 2011 Skoda Fabia mk2 picked up after my Saab 9-3 motor went completely dead last week. 
And im a bit nervous now about unfamiliar sounds. 
The car has 200k km on it, serviced by the dealer. 
But it has this constant fan sound from underneath the car, I cannot pin point it but it’s the only sound you hear in the car. The engine is really quite. 
It’s directly when you start the car with a cold engine also, radiator is not on, ac is off, blowers are off. But the sounds is pretty noticeable. 
I first thought that the radiator vent was malfunctioning and constant on but this isn’t the case. 
Any idea what this noise can be?

Edited 21 July, 20241 yr by Vyndrox
Typo

It could be the fuel pump in the tank, try using your ears to pinpoint where the noise is coming from.

It’s more in the frontish of the car then the rear. You can hear it better from under the car then in the engine bay. But I cannot spot anything suspicious. 

There isn't anything under the car like you describe so unless you can pinpoint where the sound is coming from then there's not much to be done.

Yeah understandable, I’ll make a video soon. Hope that the mic won’t cut out the fan noise in a noise reduction attempt. It’s like a quiet vacuum machine. Perhaps I can even find the source in the attempt of getting close to the noise. 

Herewith the noise. 
I’ve also noticed that the vacuum sounds gets an higher pitch when using the big lights. 
And when driving the pitch/speed increases when just coming to a stop around the 1500 rpm. 

 

youtube; 

 

Also hooked the Fabia to an OBD scanner and got these outputs;

when unrelated I just make a split post about it - I don’t have any warning ligths btw;

 

16251 [0x003F7B]

P029900: Turbo/Super Charger Underboost

Status: Confirmed, Test not completed since last DTC clear, Test not completed during this operation cycle, Warning indicator requested

----------------------------

15980 [0x003E6C]

P023600: Turbocharger Boost Sensor (A) Circ., Range/Performance

Status: Confirmed, Warning indicator requested

 

 

Edited 23 July, 20241 yr by Vyndrox
Wrong info pasted

Sounds like an air/vacuum leak to me.

Perhaps related to the underboost?

Could very well be, have a good look around to see if anything obvious has blown off the turbo or intercooler and check all the smaller lines, check the map sensor is seated correctly which I believe is mounted straight to one of the boost pipes but could be wrong.

Thanks, I’ll check it tomorrow and post an update here. 

Couldn’t find anything with just the motor hood open. I’m trying to hire a DIY garage this afternoon so I’m able to lift the car and check underneath. 
 

I’ve also done a run with the car with OBD2 enabled to see some more details, but I don’t see anything off, it seems the car still produces normal power. 
 

 

Well today I had the car on the bridge and removed the bottom plate, but unfortunately no leaking pipe/hose was found. It all looked healthy and dry too.

The sound was also not made that far down, so I couldn't find it by hearing. It seemed to be somewhere between the exhaust and the dashboard. But I have no idea which components are there and possibly the culprit.

I have scheduled an appointment with a VAG garage for the day after tomorrow and they will look at it.

 

ill post an update here afterwards. 

I am following this post with interest as my car makes a similar sound which I have always attributed to the auxiliary belt.

Well as promised herewith my update, went to VAG specialist and had a very nice mechanic that took the time to explain and check everything. He read the same error codes as me, checked the rest of the values but they seemed to be just fine like boost pressure and blockage due to contamination. 
Then went ahead with replacing both the sensors but this didn’t change anything in the values which were being read. 
The old sensors had black stuff on them, so he gave those a proper clean. Cleared the codes and toghether took it for a drive and the codes didn’t came back.

For the sound it was the hydraulic/electronic steering pump at the front left wheel. Nothing to worry about. 
 

I bought a bottle of cleaner from TUNAP from them and they gave 50% discount on the 2 hours of labor because we chatted a lot. 
 

Glad I got that sorted out. 

 

14 hours ago, Vyndrox said:

For the sound it was the hydraulic/electronic steering pump at the front left wheel. Nothing to worry about.

Thanks for that. I try not to worry about noises. I was once driving an old Ford up to Aberdeen and I could swear the big ends started knocking. I was in two minds whether to turn back. And sure enough, 20,000 miles later I crashed into a truck! I hear noises in the car that my non-driver wife doesn't. I only worry when she says, "What's that noise?".

Edited 27 July, 20241 yr by Jocko
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