Intermittent blowing fuse on fuel pump circuit

[Clavdivs]

Fuse keeps blowing on fuel pump circuit, sometimes 3 times a day, then it's OK for 10 days. I've changed the fuel pump ans fuse lasted 7 days, no obvious signs of any cable damage. Any ideas? It's a 20A fuse now, and has other things on the curcuit like injectors I think.
1.0 '94 Polo.

[passat boy]

Fuse keeps blowing on fuel pump circuit, sometimes 3 times a day, then it's OK for 10 days. I've changed the fuel pump ans fuse lasted 7 days, no obvious signs of any cable damage. Any ideas? It's a 20A fuse now, and has other things on the curcuit like injectors I think.
1.0 '94 Polo.

How about removing the earth strap on the front right of the battery behind the headlight and cleaning it with sandpaper as they rust easily and then and check&prefrably clean all other earths the same way but apply a little copperslip to all earths to keep corrosion at bay.check the rear tail light earth(near right cluster) and make sure the taillight seals dont allow water in as the bulbs corrode and cause shorts or high resistance on the posotive circut also.remove and check all bulbs.last is the fuse box and its earth,is everything secure and not coroded as damp areas in the footwell can help rust along in winter with the heater on.