poor running after standard airbox fitted?

[Phil18t]

my friend has an audi a3 1.8t AGU, he bought it with a k&n induction kit already fitted..today he asked me to fit his original airbox, after doing so the car ran poor and put in a fault code of 00544 maximum boost limit exceeded?? so i refitted the k&n and it was fine again.. any1 know why that would happen?

[mar_k]

Has the car been remapped?

If it has perhaps the standard paper filter is causing to much of a restriction and making the turbo work harder to get the air it needs into
the engine?
Try a decent panel filter

[cullygti]

standard filter didnt cause any probs on mine after mapping is the ignition amplifier good

[Phil18t]

no its not been remapped..think its got quite a newish ign amp on it.