How to force a filter

I have created categories from menu item with persistent filter and this menu module is placed under directory view(not category list view). Does it make different?

Module?
The filtering module?
Currently the filtering module ignores persistent filters

What I am saying is.. I placed categories menu in module and this module is placed under directory view.

So If you click Used car menu(directory view) then you see all the car brands list, and at the bottom, there are menus(categories) in module for Car Body Type.

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Hello,
make sure you have the desired persistent filter e.g. 52#1

and then please send me the ID of menu item
and i will log onto site to test this

menu id 20 -> menu item id 329

to brandonking:

i tested with URL:

/index.php?Itemid=329

and the filter is applied in the SQL statement, if you also make the filter visible and also the value exists in current item listing (at least one item has it) then it will also appear as selected inside the filter

So
-- make the filter temporarily visible while testing
-- also clear cache/disable cache (i have disabled it on your site) before retrying and maybe click CTRL-F5 OR shift-Reload to try to bypass any transparent proxy server if one exists