Buy Astonish Engine Degreaser from Autohub.pk or Luxobizspa.
Spray it on the engine bay, let it settle down for a few good minutes, let it get ‘foamy’
Agitate the sprayed the area with a detailing brush (a toothbrush works too).
Then you can either wash the engine degreaser with water or just clean it with some old damp towel/cloth.
Astonish Engine Degreaser has received positive feedbacks from many Pakwheelers.
Cheers.