What causes this engine cold start misfire

2015 Audi A3 CNTC engine
Cylinder #3 was misfiring when the engine was cold.
Swapped plugs and coils, no change.
Performed compression test, found all the cylinders passed compression test when the engine was hot.
Cylinder #3 compression was lower than specification only when the engine was cold.
Removed cylinder head cover and inspected the valvetrain, found cylinder #3 intake valve spring is broken.

[@LakshmanWeerakkody-wg3se]

Dear friend, I have a problem in my car, replace everything of plugs, coil packs, petrol filters, an sencers as well,. But now, What causes a car engine missing on the first few drives of the day? Once it gets to the correct temperature it runs fine with no errors, please tell me how to fix this, thanks a lot,

[@husseinalhasani]

Thermostat is always open

[@kuli2078]

Hi.
Misfire when engine is cold? Or just on coldstart 1 minute with higher rev.?
I have misfire on first cyl. when first coldstart with high engine revs. When revs drops on normal, misfire stop.
Then sometimes i have misfire with constant engine revs while drive on first cyl, when accelerate or decelerate no misfiring.
Engine 1.4 tsi twincharger
Spark plugs, coils, wiring, injectors new or good, timing good too
engine compression pressures 12 bar on all cyl.
consumption 7.5l/100
Oil and coolant does not leak
No faulty codes, just 1 cyl misfire

[@powerhounds4399]

Decoke intake valve stems

[@kuli2078]

@@powerhounds4399 i will try, thank u

[@husseinalhasani]

Thermostat is always open

[@kuli2078]

@@husseinalhasani it was carbon buildup on intake valves