I have a mk4 fiesta ztech and when I use main beam fuse for left bulb keeps blowing but right side is fine I have changed fuse and bulb and still blows so tried a bigger fuse and it's still being a f#cker. Plz help

 

there is a problem somewhere,putting in a bigger fuse is risky the fuse is rated for a reason putting in a higher one can set the car on fire it sounds like the wire has worn and is earthing out somewhere

 

Unplug headlight then try it. If it doesn't blow then you know the problem is inside headlight, if it does, then you know it's a problem with the car's wiring loom somewhere. As said above, don't ever used a higher rated fuse!!