datastore/hook issue, long page load - please help

[postcd]

Hello,

suddenly, my vbulletin 4.2 site started loading very slow (blank page for like 15 seconds and then start loading).
When i disable modules by adding "define('DISABLE_HOOKS', true);" into /includes/config.php
Then site is loading perfectly quick.

I tried to remove above mentioned line and disable all modules one by one and site still loading slow (like 15 sec. timeout before start loading).

Which is strange. Is it something with hook system/datastore?

/archive/index.php/f-101.html - loading quickly, but not index or threads/forums

i tried to restore backup (files+mysql), but the problem persist. I tried to access site via different proxy, same issue.
Other similar vbulletin sites on same server do not have this issue.

Thank You