Conditional Formatting - VBA - Cell.value VS Selection.formatConditions

I'm having major issues getting this to work correctly. Is there a way in VBA to code conditional formatting so the entire row of a range's color is changed if the condition is met? I have about 7 different colors I'm using, but if I use the following code (only partial is shown below), it only changes the specific cell (in my case, in column A), and I want the entire row (say, A4-AI4) to change colors, dependent upon what is in cell A4.

Private Sub Worksheet_SelectionChange(ByVal Target As Range)
Set MyPage = Range("$A$4:$AI$33")
For Each cell In MyPage
If cell.Value = "LH_SAS_1603" Then
Selection.FormatConditions(1).Interior.ColorIndex = 40
End If
If cell.Value = "LH_SAT_1603" Then
cell.Interior.ColorIndex = 37
End If
If cell.Value = "MH2" Then
cell.Interior.ColorIndex = 39
End If
Next
End Sub

I also tried the following, but it never stops looping through since I obvi didn't code it correctly:

Range("A4:AI33").Select
Selection.FormatConditions.Delete
Selection.FormatConditions.Add Type:=xlExpression, Formula1:="=$A$4=$A$37"
Selection.FormatConditions(1).Interior.ColorIndex = 37
Selection.FormatConditions.Add Type:=xlExpression, Formula1:="=$A$4=$A$39"
Selection.FormatConditions(2).Interior.ColorIndex = 40
Range("A37").Select
End Sub