Question

I previously asked how I could check whether a piece of text contains a string, now I would like to delete that piece of string if it is found in that cell.

If the value in column C is different from column W, I check whether
column A contains “MIG”, if it does I add it to the cell, if not I do
nothing.

Because this macro is run everytime you save, if you were to edit the values in W & C to make them match then column A will still say “MIG”.

So when the document is saved, the macro will now see column C & W are
the same and if it contains “MIG” it should delete “MIG” from the
cell.

Sample

If shtVO.Cells(Row, 3).Value <> shtVO.Cells(Row, 23).Value Then
  If shtVO.Cells(Row, 1).Value Like "*MIG*" Then
  Else
    shtVO.Cells(Row, 1).Value = shtVO.Cells(Row, 1).Value + "MIG"
  End If
Else
  If shtVO.Cells(Row, 3).Value = shtVO.Cells(Row, 23).Value Then
    If shtVO.Cells(Row, 1).Value Like "*MIG*" Then
        .....              
    End If
  End If
End If

Answer 1

Not sure I understand your logic, but to clear a cell value use

shtVO.Cells( ... ).ClearContents

EDIT

Use of Replace

shtVO.Cells( ... ).Value = Replace(shtVO.Cells( ... ).Value, "MIG", "")

The rest of your comment deals with the possibility that you are left with double space after replaceing MIG
Eg "Fisrt MIG second" –> "Fisrt  second"