I have a peugeot 207 1.6 HDI ?

hi had my 207 3 months and my depollution light came on opened the bonnet to find a pipe off the top of the turbo have repaired that costing £10 the light went off for it to appear back on a month later with loss of power till turn the car off and switch back on its fine drives ok but the lights still on. can any one help plz...