I will try to locate this pipe tomorrow in daylight. The problem will be establishing where on the pipe the problem is because the leakage only occurs when the car is running and I give the accelerator a bit of welly. The extra power requirement generates the problem. But thanks for your help.
I just thought I should let you guys know that the problem was a leaking Intercooler Pipe which is now replaced and all is fine. I got the garage to check the "Error Message" that I was getting "Engine Ststems Failure" and they said all is okay now - they lied! Last night when my wife was driving home in the rain she gat the same message, the car ground to a halt and she waited a few minutes and restarted the car - no other warning lights were illuminated. I feel this is an extremely dangerous thing to happen and am going to write to Ford about it. Anyway, I thank you again for your help.