Hi every1 im new to the bmw world just bought my first e90 325i m sport, could u plz help my car had started to shake n sound rough when stationery, when driving its allgood jus stationery it revs go below 8000rpm it coughs n cuts out, ive got a new coil n new sparkplug tested it in each1 but no look same thing i would really appreciate any advice.