There was a dodgy fuse in some part of the ECU which meant that it was on the limp home programe all the time, so it ran really poor, it took my local ford garage three goes to diagnose the problem, as the computer on the car wouldnt talk to the diagnostic machine, it was only by chance when they check the fuses that they found one was bust. Not quite sure why it went to limp home but as soon as they changed the fuse it was like a different car, didnt idle all over the place and pull like a train. The mechanic siad he'd never known it happen before mine