Check post #16 in this thread. For a brera but basically the same fault. Check wiring for voltage , maybe try to lubricate or a new throttle body. There is a MES actuator test which can show if the valve is working or not.

swirl flaps servo motor/actuator

I have a 1.9 JTDM with a strange churning noise at 2000rpm plus the occasional misfire: the noise appears to be coming from behind the bulkhead and it sounds to me like it could be the servo/actuator rather than the manifold swirl flap mechanism. Does anyone who has experience of the parts know...

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Not a single hit for that code in the G forum.

 

could've gotten frozen.

 

Like it, often it is the simple answer which is right! The air being sucked in could still be at -10 after 15 minutes.

 

Great input. Guess I will need to get under the hood and take a closer look, even though it's even colder today and much nicer inside by the laptop and a cup of coffee.

 

Ok, so there was definitely

ice in the throttle body. I cleaned it out, warmed it up, cleaned some more and erased the error code. I took the car for a short drive, 10-15 minutes, and at least everything seemed ok during this.
I kind of wonder though, why there was watery gunk in there in the first place…

 

Burning fuel creates water, 1 liter of water per liter of fuel burned. Part of that water makes it into the crankcase and through the pcv system into the intake, in vapor form.

Intercooler cools down the vapors, so it either freezes in there (I'm sure some does) or it freezes on any cold metal surface it encounters next, like the throttle valve.

I've had to drill a small hole in intercoolers before so the liquid water would be drained out as the formation of ice completely blocked the intake

 

Plus the water vapour just sucked in through the air filter.

same for your gas boiler ch4 + o2 = 2h2o + co2. water is everywhere!