Code running really slowly

Originally Posted by jolivanes

Just thinking out loud here.
Would this work?

Sub Try()
    With Range("E1:E8000")    '<---- Change as required
        .Replace 0, "", xlWhole
        .SpecialCells(4).EntireRow.Delete
    End With
End Sub

I tried this on a sample sheet with 16 rows, 4 of which should have been deleted. It worked but it took over 30 seconds to run.

It's looks like there's something wrong with the workbook itself. If I make a new workbook and run your script, then it works pretty much instantly....

What kind of formulae do you have in the workbook?
I had a similar problem years ago. Some functions recalculate whenever a change is made.
I changed the culprits and the problem was solved.
I personally don't know anything at all about these functions but if you post the formulae someone might be able to give you an alternative.