Model Year 23/24 Fan coming on

[DaveSmith]

I've noticed that since the change in the weather (getting colder) the radiator fan is on when I get home and park up, even after fairly short traffic free drive. For example, tonight I drove about 12 miles on open roads at 50/60 mph and a short bit of town driving at 30mph, so it was not being worked hard. The fan runs on for several minutes even after the car is parked. I don't recall it doing it in the hotter weather earlier this year or at all over the 2 years I have had the car. I have checked the coolant temperature and it is rock steady on 90DegC. I have tried it with a/c on and off and it makes no difference. Checked coolant level and it is OK. Also noticed a marked drop in mpg which might not be related to the issue and just cold weather.
Car is 73 plate 2.0TSI 190 Petrol.

 

[DEAN0]

I believe it happens in conjunction with the aux water pump.
When you switch off the car the aux pump keeps pushing water around the turbo so it doesn't cook the oil now sitting still inside it.
The cooling fan comes on to remove the heat.

 

[DaveSmith]

I believe it happens in conjunction with the aux water pump.
When you switch off the car the aux pump keeps pushing water around the turbo so it doesn't cook the oil now sitting still inside it.
The cooling fan comes on to remove the heat.

Maybe it's always done it then? Can't say that I ever noticed it until just recently though.

 

[SRGTD]

Maybe it's always done it then? Can't say that I ever noticed it until just recently though.

Maybe it’s the petrol particulate filter performing a forced regeneration to neutralise accumulated particulate matter in the filter; engine fan running and a marked drop in mpg are two of the tell tale signs.

If the cooling fan is running when you reach your destination and switch the ignition off, then the regeneration process is interrupted and will recommence on the next - and subsequent - ignition cycle(s) until the regeneration is complete.

When I had my 2.0 petrol Polo GTI+, other tell tale signs in addition to the two above were;
- a deeper exhaust note
- a ‘hot’ smell from the exhaust
- hesitancy a slight lumpiness when moving away from rest and a slight reluctance to accelerate
- stop start is deactivated

 

[DaveSmith]

Maybe it’s the petrol particulate filter performing a forced regeneration to neutralise accumulated particulate matter in the filter; engine fan running and a marked drop in mpg are two of the tell tale signs.

If the cooling fan is running when you reach your destination and switch the ignition off, then the regeneration process is interrupted and will recommence on the next - and subsequent - ignition cycle(s) until the regeneration is complete.

When I had my 2.0 petrol Polo GTI+, other tell tale signs in addition to the two above were;
- a deeper exhaust note
- a ‘hot’ smell from the exhaust
- hesitancy a slight lumpiness when moving away from rest and a slight reluctance to accelerate
- stop start is deactivated

Nail hit squarely on the head I think.
Exhaust note yep, start/stop enabled but not functioning yep, hesitancy yep. I'll check the exhaust smell next run.
You are a steely eyed missile man.