Engine misfire

  1. #1
    Misfire mostly happens after exiting roundabout / sharp corner accelerating away. 3 error codes show as mixture too rich AND mixture too weak and engine misfire. If I dip clutch, switch engine off then on it clears. 3 x garages stumped, have changed coil, plugs and replaced big bore back silencer with normal one at major cost without any improvement. Any help appreciated before another garage rips me off.