Engineering colloquialisms.

Maybe it’s because of industry-wide mediocre documentation of customer requirements. Or maybe it’s because of a dearth of automotive systems engineering prowess. But there are phrases that act like quasi-requirements which bounce around the halls of manufacturers without a traceable link to a customer requirement and a mediocre understanding of the originally-desired need. For instance, nearly all automotive engineers use the term “firewall” — despite the desperate cries of corporate lawyers begging them to stop — but few understand the name derives from steam-powered vehicles where a solid-steel panel separated the driver from the boiler’s fire as a safety precaution. Or the term “dash” – which lawyers also despise since juries might misconstrue its usage as a euphemism for dashed skulls against the panel’s surface – is used to describe the vehicle’s instrument panel (IP), but the term derived from a horse-drawn carriage’s dashboard, which protected the driver from the splaying of mud and debris. These needs or requirements were either lost or morphed over time, but the terms persisted.

Suddenly, though, one such term has a rejuvenated reminder of its original meaning: “ratholes”. Fit and finish engineers for decades have used that term casually to discuss undesirable gaps between parts without truly realizing that the stakeholder requirement was to avoid openings that allow for destructive rodents to squirm through and wreak havoc. But as the pandemic wanes and warmer weather in the northern hemisphere starts to permit socially-distanced hermits to escape their cabin fever, damage to vehicles from rats have become the undesirable sequel to Covid-19.

“Car owners often don’t realize that a rat or mouse is living under the hood,“ states Keith Canete, the Master Automotive Technician at YourMechanic.com (an at-home car repair provider), “until they smell a pungent whiff of urine waft in through the air conditioning when they start the engine, which would indicate that the rat or rat colony has been there for a while. Rats are opportunists that tend to pick cars that have been parked idle outside for a week or longer in order to build themselves a cozy home under the hood.”

An Ounce of Prevention

The next obvious question is how to avoid such an odiferous and financial disappointment. “To prevent a party of uninvited rodents from settling in your engine, be sure to drive your car at least once a week and never leave any food in the vehicle because rats have a keen sense of smell and will target your vehicle if there’s any morsel they can smell.” Canete additionally adds, “If you want to go the extra mile to prevent a rat infestation under your hood, you can spray your vehicle with a peppermint spray or install an ultrasound that emits a high pitched noise that only rodents can hear that repels them.” 

Or you can remind your friendly, neighborhood engineering person who‘s devising the next generation of intelligent vehicles to avoid building any ratholes.