Can anyone shed any light on why my MY97 Impreza hesitates when on fast idle? When accelerating while engine is cold car hesitates and seems reluctant to accelerate, as soon as the tick over drops to normal idle rpm car drives fine, Fitted a new MAF a while back due to constant hesitation but new MAF fixed this, Any ideas?

 

simalar problems on mine, check your error codes, could be the ecu's water temp sensor or the throtle sensor.