Cadillac Repair: Rear shocks, 85 Deville, monroe struts, sudden depression

Question
Greetigs,
1985 DeVille, automatic leveling rear.  It needed rear shocks so I had Monroe struts/air shocks installed.  Monroe p/n is MON81961.  
Car leveled as needed. Now, though, when I cross a manhole cover or other sort of sudden depression in the street, the rear suspension, (either or both sides) CLUNKS.
Did not do that before.  
Had it checked by same mechanic for looseness.  He thinks the air is not being pumped in enough.  This seems opposite to the symptom since that would just push down harder.
Seems to me the shocks are not holding the wheel from dropping.  Does this make sense?
To humor the mechanic, we might install hoses for manual air fill since I do not load the trunk much anyway.  Wish I had gone to regular struts/shocks.  What would be the effect of not even adding air to the shocks?
Thanks in advance.

C Barlow

Answer
Squeeze the rubber portion of the air hocks and see if there is any air in them.

When you turn ON the ignition switch in the morning can you hear the air pump running ?.

If you feel NO air in the air shocks and you can physically see an air line attached to each shock, Your problem is most likely a faulty:

air compressor.

Level control sensor .

If you are mechanicaly inclined or know of someone who is, You will need simple electrical schematics, Test procedures and picture locations of the components within the system that is causing you problems of which can't be done on this website which only allows one picture. I do not have a website so you will have to e-mail: onlineautohelp@msn.com in order to obtain the information.