Spraying the undercarriage with something unpalatable worth a try?

The only thing that works IME is killing them (humanely).

https://www.consumerreports.org/cars/car-maintenance/how-to-protect-your-car-from-rodents-a5816950285/

Perhaps rats will not chew wires sprayed with cayenne pepper or one of the other anti-rodent sprays sold for this purpose. Keeping the wires sprayed might be a mild hassle, but there are also tapes etc.

We used a product called mouseaway to keep rodents away from vehicles and our pool equipment.

https://www.collegehillshonda.com/mm...4019-23172.png

Honda Rat Tape, lifetime supply

Rodent tape is a deterrent for critters that like to chew vehicle wiring. Wrap any trouble spots to prevent any future wire harness issues. The tape is treated with capsaicin (active component in chili peppers). When wrapping the harness it is recommended to use the half-wrapping method. Each time you wrap the tape around the harness overlap the previous layer by half the width of the tape. One roll = ~65 feet of tape.

Our Price: $45.90
Part # 4019-2317

The second time my wife's car got attacked. We gave the dealer a similiar tape to put on the area that had been chewed. That area has worked great. The third time they found a new area to destroy.

The only thing - in NYC - my buddy found that worked with his Honda was selling it and using Zip cars.

He got tired of $1500 bills to fix, and nothing stopped them chowing down. Cover one bit they found somewhere else. GL…

That's the shock trap I bought. Cheap POS. I've handled everything with new gloves wiped in peanut butter oil to remove my scent. It's tough.

Hiring it done is actually not a bad way to go. I mean a pest control company has to give some kind of guarantee that they can do the job and keep coming around as needed. Some are really aggressive like removing all loose blown in attic insulation which is a lot of money. I'm sure that's one way to do it but not the only way.