There are some relays that control the wipers, but I don’t see how a problem there could take out the washer pump, too.

Note in that diagram (section 13.1) you will see two pumps. The windshield washer pump is obvious, that sprays the windshield. The second is a little confusing. It’s called the power wash pump and is for the optional headlight washers. Don’t let that confuse you when troubleshooting.

The next time the car acts up, try to operate the front passenger window or adjust the right side exterior mirror. Both get their power via Switched System Power Relay #2. See figure 01.3. If that relay were to act up, you’d lose the wipers, washers, front passenger window, and the right mirror. Since the mirrors are already set, you’re not going to notice if one is intermittently dead. Same with the window, as you’re not likely to open it in the rain.