Cold start, running really rough
 

Hey guys just wondering any thoughts on my issue. 05 Sti just been serviced when I start from cold it sounds like it's missing and struggles to get much drive in gear. Also getting flutter at 2500 which is about 1500 rpm lower then usual. All seems to be fine once it's warmed up. Any thought would be great cheers Taylor.

Take it back to mechanic and get it assessed if this is a new issue. May be as simple as something not tightened properly.

Antilag to keep it spinning up?