On a journey back from North Wales to Leigh Lancs about 70 miles my car just lost power after about 50 miles and I had to pull onto the hard shoulder,the car did not cut out, but whilst trying to accelerate it would not pull. I switched off the engine and left it for 4/5 mins, no success, tried again 2mins later and away it went, no more trouble all the way hame. It is a 4/4 1.8 zetec engine [2003]. Any ideas please.