Thanks for the suggestions it is greatly appreciated. I am based in Norwich. Basically the car runs absolutely fine apart from the one problem mentioned. It starts OK and runs smoothly without any missing or harshness. The only snag is this hesitation. The strange thing is the car actually seemed to be performing better than ever recently which would seem to tie in with Tim's suggestion. When the car is stone cold there is no hesitation. Once the temp gauge reaches 60 upwards the symptom will appear. Pull away from a roundabout or traffic lights with an average throttle opening, (remember i'm the one who gets good milages out of Dunlops so lets change that to conservative opening), and the car pulls really well, normally up to about 1700 revs or so. Bit hard to be exact as the rate increases quite quickly in first. The engine will then suddenly lose power. It doesnt cut out its just as if you have reduced the throttle opening. Keep your foot on the same place on the throttle and it will suddenly zoom away again always within a second or so of the fault occuring. If you hold first this pattern may be repeated at 2500 rpm or so but I would normally go to second at this point anyway. Symptom is then repeated in second but not the higher gears. Once up to speed, say 70 on a dual carrageway, the car will sit on cruise control and perform perfectly. The fault only occured after I cahnged the run on pump, (yes brushes down to the wire). I have looked at all of the pipes in this area and they all seem in place and tight but I will double check as it seems too much of a coincidence. I will also check all of the electrical connectors in that area. There is no engine management light on. Will keep you posted how I get on. If all else fails I will book it in and let you know what the cure is. On a seperate note this forum has been great since I found it. It has saved be a fortune on the aux pump and I also checked the wiper linkages after reading so many posts. When I took them apart the passanger side one was close to solid. Now all copper greased. 2001 , Diesel 115bhp, Galaxy Ghia, 96K hoping to keep to 130K at least. (Kids to fund through uni)