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.

[kuli]

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