Ive had a new 59 plate Fiesta for about a month now and I know this might sound like a daft question but should the petrol cap lock when the car is locked, its got that new capless system and anyone could siphon fuel out.
Thanks in anticipation.

I am surprised that there have been no replies to this during the past year!

I now have a Fiesta and asked the same question. The engineers at the local dealer immediately told me that the fuel flap should lock - which is doesn't - but were later corrected by head office who told them it does not and should not because of their new system - which is supposed to be tamper proof.

However I have since proved that the system is not tamper proof. You can quite easily get in past the spring mechanism. Once in, fuel can be syphoned out using a tube. Once the fuel in the tank is below a certain point it appears that you cannot syphon fuel - maybe due to the shape of the tank - but that does not negate the fact that it can be done - I have seen it done on my own car, as an experiment. Similarly one could pour what they wanted into the tank.

Ford do not seem bothered about my complaints, saying that is how it, they cannot do anything (although I do know of someone who had it changed longer ago). They seem to think it so remote in this day of high fuel prices that an unscrupulous person would think of stealing fuel from an unlocked fuel tank, saying that if anyone wants to steal your fuel they will steal it. Maybe, but the more barriers there are, the less likely they will bother but will move to an easier target, surely they can see that.

I will say that my local dealer seem to have now accepted that I have a point, but say that they cannot get the parts to actually change the mechanism. I am sure it could be done but it needs someone willing to work it out.

If you have this problem can I suggest that you complain to Ford. If enough people push this, maybe they will accept there is a problem and do something about it. I have heard that they have modified the Mondeo now to include a lockable flap, due to complaints, but I have not confirmed this myself.

One final point, the Easyfuel system has been advertised by Ford as a new innovation which prevents owners from filling up with the wrong fuel due only accepting the nozzle of a diesel fuel pump. This idea is not so new - a few years ago I had a diesel Astra which had the fuel tank inlet shaped in order to only accept a diesel fuel pump nozzle - and the fuel tank locked with the central locking. So the idea is not so new after all.