Hi

Car came in with with a loss of power. plugged in and found that the butterfly bypass valve didnt work so fitted new one car ran fine next morning customer arrived to collect and engine management light was on and it now has a egr fault but i tested the egr on live data and it seems to be operating fine. can anyone help as it is the first one of these peugeots ive worked on and i dont want to fit a new egr if it wont fix the problem