I also have the same problem of flashing glow plug light - first appeared in Feb 05 only 4 months after I bought the car! Then again in April 05. Cured it initially by having one of the injectors reprogrammed at a cost of £70. Now it's returned again - 1 week ago. This time Ford want to replace the injector - a whopping £400 including fitting for just one injector. If this cures it for good I'd be happy - but I'm not sure I want to take the chance that the other 3 injectors will follow suit!!!