96 C280 Vacuum Modulator?

[Martineau Gauda]

Hi,

Now I am on to checking vacuum lines and the transmission vacuum modulator for vacuum leaks.

The procedure I am familar with on other cars is to put 20 inches of vacuum on the line going to the vacuum modulator and see if it holds vacuum.

Is this the procedure that I should use on this car and how much trouble is it to change the modulator? Is this an item that should be changed at 100,00 miles or less?

What is the acceptable length of time that the line should hold vacuum?

Thanks