A friend of mine has purchased a new 1.4 petrol C3 it has only done 3000 miles since new and has had the head gasget replaced after a week because of an oil leak . Guess what the oil leak is back and it seems to be from the area behind the Air con pump, he has tried to indentify exactly where the oil is coming from but cant find the cause without stripping components down. Could it be from a threaded hole in the block that has a stud or bolt missing , have any of you that work in a Citroen dealership come across this problem.