Problem removing wp-cache plugin

I recently removed the plugin wp-cache. A few days after removing it I started getting occasional “error establishing a database connection” errors. These errors appear to be random and they happen about every 20-30 clicks.

As suggested on the support page for wp-cache (http://mnm.uib.es/gallir/wp-cache-2/), I removed the following line from the wp-config.php file:

define(‘WP_CACHE’, true);

I have contatcted my host and they have verified that the database server is fine and I have doublechecked the user name and password settings.

I had to remove the wp-cache plugin because my site was experiencing “delays” to changes. When I changed something on the site it would sometimes take 30 min to an hour before it would show up and it would show up at different times on different pages. This still happened after deactivating the plugin, but it stopped happening after I removed the plugin and the plugin call from the wp-config.php file.

I have read elsewhere that it is a bad idea to change the wp-config.php file after the WP installation is complete, but I don’t know of any other way to remove this plugin.

Any help would be greatly appreciated.