I noticed while my car was up on a lift that there were some slots/holes in the bottom of my front fascia/bumper. Is there supposed to be a splashguard or weather-striping under there? I haven't been able to locate a diagram of that area with part numbers. Your help would be appreciated.

 

You can see parts diagrams online at any honda or acura parts websites. There are quite a few of them.

There are slots on both bumpers, that is just how they are made. There is an engine undertray, but that is basically it. CL was probably only Acura or one of the only to not offer a OEM lip kit.