I've just bought a 56 plate 1.8 TDCI focus sport and have this problem. When shpwing me around the car, the owner managed to open the bonnet no problem, but since taking it home, I've not been able to open it!
I've tried to follow this guide - I've managed to get the rubber boot, get a screw driver into the white collet and give it a good old push, but nothing.
Maybe I'm not pushing on it hard enough? How hard to i physically need to put into it? What are my options if I can't get this off? Am I gonna have to smash in the grill to open the bonnet, or is it gonna be a costly garage fee?