I have a 2001 Toyota Highlander and want to know how do rid mice from undercarriage of car?

Drive it would be my first suggestion…preferable through water.

Shotgun will work but the results will be expensive.

Your state’s Department of Agriculture office has experts in rodent control. And their services are free. You might want to look them up.

The undercarriage is outside the passenger compartment, right? So the mice, should any be there at the time, will likely jump off once you start the car.

If the mice are in the passenger compartment, you have to do what every homeowner already knows. Find all the places in the perimeter of the passenger compartment having holes big enough for a mouse to move through. Small mice can move through a hole the size of a nickel. So for any hole that size or bigger, you have to plug it. New cars shouldn’t have any of these holes, so if you find one, that’s a place either a change has been made by a mechanic, or a mouse has chewed his way in. If the former, have a chat about your expectations with your mechanic. If the latter – well – mice will be mice.

Once the perimeter is secured, then you can either trap the mice remaining inside, or rig up some kind of one-way door so they can get out, but not get back in. They have to leave daily for food and water, so if you have a one-way door rigged, in a day or two they’ll all be gone.

To prevent this from happening again in the future:

  • Don’t park in areas mice are known to inhabit.
  • Don’t leave food substances in the car at all, or at least overnight. Especially substances that smell good to a mouse, like peanut butter, chocolate, cheese, etc.
  • Inspect all mechanic work done to make sure no mice-entry holes were created.

Cats like mice or at least like to play with them a while before killing them. Expect the cat to bring you a proud trophy though.

As a note, new cars have plenty of holes that mice can get into. They really like to squeeze down into the HVAC intake and then get trapped on top of the cabin filter and die so that it smells terrible every time you turn on the blower.

I have all open fields behind me with plenty of mice and other critters. I have lived in this house 47 years and never had a mouse bother any of our cars. Is yoours being damager by mice?

I dealt with mice in engine compartment once. Suggestion was to get a few cans of chewing tobacco, punch a few holes in the top of each and put tape on the bottoms to stick them in different parts of the engine bay. Near as I can tell, it worked to keep them out. The tobacco dried over time, but still smelled for a while. Easy clean up by removing the cans.

I’ve had one mouse attack (wires) on a vehicle in 40 years at the same house. It must be rare and random.