How to resolve glow plug error ? It says flashing lights means problem with Ems.Can this be sensor issue?

Scan it with VCDS and see what faults it brings and then take it from there.

Check the brake lights are working, if not then it's s faulty switch on the pedal. 

 

If if they work ok then you need a scan as the flashing glow plug light has multiple meanings. 

Thanks for replying.

 

Also there is sudden loss of power while driving and also this has started after the flashing of glow plug light error..is this coincidence or some major problem with engine or ems?

 No coincidence, it is connected, get the car scanned with VCDS.