banyak punca bole jadi macam tu.. maybe you can check all sensors connnertor and make sure no leak vacum hose..the best go for diagnose test kat merc specialist workshop to ensure faulty error.. good luck..
Actually the 300SE always have this problem.Better send to Merc specialist to diagnose test.I own this same model too,i also have the same problem,i have a very good mechanic already help me fix the problem.