clattering noise 1999 scenic

Hi hope someone could help me please? I have a 1999 megane scenic 1.6 16v alize 175.000 yes aa lot of miles but engine runs sweet and passed MOT last week with 1 advisory anyway back to the problem my wife pulled into the petrol station filled up and when she drove out the car started to make a metallic clattering noise from front drivers wheel area it would come and go and is quite loud I took the car for a drive all was fine till I came upon a bumpy bit of road and it started I took it out of drive still there pressed brakes still there so took it to a car park did tge the full lock check thinking it was the cv joints but all quite ive checked to see if anything is loose all looks ok so am quite puzzled anyway thankyou for taking the time to read this I hope someone can help as the car is a life line thank you again rich also ive revved engine but all is quite