Driving home on the motorway I went to overtake and .. nothing. Pedal to the metal, made no difference, just kept pootling along. AHA says I, due for a filter service , getting insufficient diesel. So today I drove (gently) to get filters, and fitted new diesel and air filters. 30 min, no hassle. Took car out to test it, and it seemed to be fixed, accelerating nicely uphill, then all of a sudden .. continued running fine, but flat as a pancake, no response to flooring the accelerator. No s