Sub remplacer()
Dim trouve As Range, dl&
With Feuil1
dl = .Cells(Rows.Count, 1).End(xlUp).Row
Set trouve = Range(.Cells(1, 4), .Cells(dl, 4)).Find(.[M2], LookIn:=xlFormulas, lookat:=xlPart)
If Not trouve Is Nothing Then
fa = trouve.Row
Do
trouve.Formula = Replace(trouve.Formula, .[M2], .[N2], , , vbTextCompare)
Set trouve = .Columns(4).FindNext(trouve)
Loop While Not trouve Is Nothing And trouve.Row <> fa
End If
End With
End Sub