Pakistan is automatically eliminated if: New Zealand beats England. If NZ defeats England they would reach 5 points, which Pakistan cannot touch. And then NZ and England will be the two teams to qualify for T20 WC semifinals.
If Pakistan loses to Sri Lanka in their final Super 8 match or their match is washed out due to rain, it is all over for the 'Men in Green'.
Advantage for Pakistan: Pak plays the final match of the group (Feb 28). This means they will know exactly what margin they need to win by after seeing the result of the NZ vs England game on Feb 27.