Nest building, hoarding, having babies and gnawing on everything in sight are year-round occupations for rats. You might not realise that this has anything to do with your car maintenance, but it can.

Aside from the smell and hygiene concerns in having these winter hitch hikers take up residence in your car, the real concern over these uninvited passengers is the surprising amount of damage they are capable of doing to your vehicle. Rats have been known chew or damage a remarkable range of car components and accessories, including wiring, belts, hoses and even plastic storage such as windscreen washer bottles.

At this time of year food becomes scarcer and nights get cooler; rodents are looking to upgrade their digs.  They are doing their best to break into garages, sheds and even homes if they can.  An engine bay might seem like a dangerous place for a rat family, but from their point of view it’s perfect.  Rats are active at night so once a car is parked for the evening the discerning rat has an easy choice – cold garage or nicely warmed engine bay.  Then he invites all his friends over.  If you have kids that leave the car in a similar state to mine, then the smell of sticky leftovers makes for even hotter property. 

While it is the shelter that attracts, it’s all your expensive wiring and hoses that entertain.  A rats’ teeth grow continuously and to keep them short and sharp they must chew.  Electrical wiring is the perfect squishy but firm teething toy.  Modern cars have more wiring, modules, computers and sensors than ever so extensive damage can happen in a short space of time.  Some manufacturers are also introducing a new ecofriendly plant based (soy) insulation material as an alternative to petroleum based plastic coated wiring.  While there are reports of rats favouring the new flavour and seeking it out, in my experience soy marinated or not rats like wires and will happily chew either.

Perhaps the worst case was a rat that had crawled up the air vent and died deep in the air-conditioning system.  The entire dash had to be removed to get that one out.  Keep this in mind if using baits as you don’t want one to die somewhere inconvenient.

The question of how to prevent rodent damage is difficult and depends on your situation.  We are about to trial a Capsaicin (from chilli’s) infused insulation tape which is used to wrap essential wiring; let’s hope it works otherwise I’ll just be adding an extra spicy kick to the soy flavour.

I would suggest checking under the bonnet between services for signs such as nesting material, damage and droppings.  Lock up any food sources such as dog biscuits that might attract rats to your garage.  Traps and repellents are available online.  Cars are more at risk if not driven regularly so be extra vigilant if you have a car in storage. If you find a problem at your place it is a good idea to talk to a pest control professional and have any damage repaired immediately.