Ive been sent this to look at for another garage that has had several things done to it,"logged map sensor so fitted genuine vw still logging sensor check if its got all the correct earths and voltages, checked for air leaks all ok sent ecu for testing all ok" now all ive done is scanned it and it says Map sensor incorrect signal I suspect an air leak but not sure where, is there any common places cannot get my head round it today will look again tomorrow

Thanks