'08 Impreza misfiring?

[MZ]

'08 2.5l 170hp, 5sp, <2k kms
When cold, does not accelerate smoothly - seems to be "missing." Fine once
it's warmed up. No codes or lights.
MZ

 

[Carl 1 Lucky Texan]

'08 2.5l 170hp, 5sp, <2k kms
When cold, does not accelerate smoothly - seems to be "missing." Fine
once it's warmed up. No codes or lights.
MZ

Have the codes read anyway. Have the Engine Temp Sensor (not the 'temp
gauge sender') tested' (still in warranty - right?)

Carl