The Skoda Superb and all TSI VAG cars make some strange noises that you may have been wondering about.

 

• Opening doors: Beeping? Buzzing,  short duration few 1 - 2 seconds or so at a time. From the front of the engine - This is the high pressure fuel pump priming to ensure a smooth start.  Why it primes when you open the passenger doors is a mystery IMO. You go to get something out of the car, or boot and off it goes  

 

 

 

• After shutdown: Electric motor running, long duration up to a few minutes. From the back of the engine - This is a coolant pump circulating coolant to the turbo and cylinder head and preventing oil sludge buildup in the galleries, particularly in the turbo main bearings. 

 

 

 

 

Edited 9 June, 20197 yr by digifish

Interesting ideas. 

 

I think it’s more the low pressure fuel pump though (aka in tank lift pump) priming. Petrol VAG cars have done this since the 90s. The buzzing and clicking under the bonnet on shut down is normally the throttle valve cycling.

23 hours ago, Tech1e said:

Interesting ideas. 

 

I think it’s more the low pressure fuel pump though (aka in tank lift pump) priming. Petrol VAG cars have done this since the 90s. The buzzing and clicking under the bonnet on shut down is normally the throttle valve cycling.

 

It's definitely not the low pressure tank pump. Its coming from the front of the engine.

29 minutes ago, digifish said:

 

It's definitely not the low pressure tank pump. Its coming from the front of the engine.

 

Fair enough. VAG cars historically have always ran the low pressure lift pump in the tank to ensure pressure at the rail ready for start. Normally the high pressure fuel pump on the engine is mechanical. 

There are far more noises than that, SWMBO doesn't like sitting in the car on her own when the ignition has just been turned off (as she does when I nip into a shop).  The clicks, buzzes and whirrs last a minute or so as the car shuts down  and she thinks it is alive.

 

 

4 minutes ago, IJWS15 said:

she thinks it is alive.

 

**NEWSFLASH**

 

It is