Gemini 3 Pro:

This is a classic logistical puzzle!

Unless you have a very unique way of carrying your vehicle, you should definitely drive.

If you walk there, you'll arrive at the car wash, but your car will still be dirty back at your house. You need to take the car with you to get it washed.

Would you like me to check the weather forecast for $mytown to see if it's a good day for a car wash?

For me, various forms of Gemini respond with "Unless you are planning on carrying the car there" which I find to be just sassy enough to be amusing.