kevrsturbo

i have an rs turbo s2 . The problem is car wont start wen fuel meter plug is connected, just starts breifly then dies then wont start atall; but wen fuel meter plug is disconnected motor starts no problem, then after car has been running a few mins i then connect the fuel meter plug and car runs ok. then wen driving car at about four and a half thousand revs car has wat seems like flat spots. ive noticed if tht i leave the plug off while driving there is no flat spots. i have changed the fuel meter four times and same fault occurs , change fueling ecu to , anyone any ideas.