[shorod]

Be sure to only insert the straw/Q-tip/cleaner into the valve portion of the EGR valve and not the vacuum port of the EGR valve. The valve portion is the metal portion that gets bolted to the manifold. As long as this is the only place you work with, you don't need to worry about puncturing the diaphragm.

If you have a vacuum gauge, you can apply vacuum to the vacuum port and open the valve, then let the cleaner do its job on the valve sealing surfaces. This will also help you make sure the diaphragm integrity is good (holds a vacuum).

-Rod