We’ve already heard that automatic car washes wreck havoc on smart cars but it appears washing an autonomous vehicle is significantly worse.

As CNN reports, autonomous vehicles need to be cleaned more frequently in order to ensure their sensors and cameras are free from road debris such as dirt, bugs and animal droppings. However, automatic car washes present an issue as they could damage expensive equipment or leave soap or water spots on cameras which are need to drive the vehicle.

Waymo is already aware of the issue and has tapped Avis to maintain its fleet of fully-autonomous Chrysler Pacifica Hybrid minivans. The company declined to say how it cleans the vans but Avis chief innovation officer Arthur Orduña said “We give them the premium level of service that I don’t think any vehicle globally is getting.”

CNN goes on to say most companies wash their vehicles manually with microfiber cloths. They then use rubbing alcohol or glass cleaner on sensitive areas. As an example, Toyota uses rubbing alcohol to clean cameras while Uber uses windshield washer fluid in colder climates. In Uber’s case, the company goes as far as blowing air on its cameras to ensure there isn’t any residue left behind.

The intensive manual cleaning probably wouldn’t go over well with consumers but a number of automakers are working to integrate the various components into the design of their vehicles. Regardless, Seeva CEO Diane Lansinger “It’s going to be quite awhile before we get away from the manual care.”