Exhaust dangers deserve your respect
What’s coming from your tail pipe is poison, and even new cars can develop problems that put you at risk
With little variance, every winter we will read or hear in the news about someone getting seriously ill or worse from auto exhaust poisoning. Carbon monoxide (the main cause of these avoidable tragedies) is branded with the silent killer tag, but with a little attention paid and some preventative steps, this lethal gas can be detected and kept in check.
Don’t assume new or newer is OK. Vehicle exhaust systems live in a nasty environment and are exposed to impacts as well as the ravages of salt, water, and our ever changing temperatures. They should receive a cursory visual inspection at every routine maintenance visit and, after only a few years on the road, a more thorough check-over isn’t overkill. The only proper way to check an exhaust system for leaks is to run the engine and partially block the tail-pipe while searching for any leaks by feel and by sound.
At the same time as the annual exhaust check, an inspection is needed for all underbody metal panels, firewalls, and the multitude of holes in them (some from corrosion and some from design). Recently a number of emergency services units in the U.S. and Canada experienced exhaust leaks into the passenger cabin of their response vehicles. Some of the concerns were traced to the installation of specialized equipment, which required the drilling of holes in various panels to facilitate wire and cable routing. These holes were found to be the cause of exhaust entry as they weren’t properly sealed against gases leaking into the cabin. If you’re arranging for any new accessories or addons that require holes to be added, make sure to use proper grommets or sealing agents.
While engine idling is frowned upon by many environmentally conscious types, it can be a fact of life during our winters. Never idle a vehicle in an attached garage for any length of time and, when idling one outside, make sure the undercarriage has plenty of clearance over any accumulated snow, and that the area around the tail pipe is especially clear. This can become critical if you’re stuck in a snowbank or ditch while awaiting a roadside service vehicle and need to idle the engine to keep warm.
Listen to what your exhaust system is telling you. Most exhaust leaks provide an audible warning, but it’s hard to hear this if your door windows are closed tight and the audio system is turned up. Simply leaving your driver’s door open (with all radio and HVAC system turned completely off) during a morning start can let you hear any trouble. Many exhaust leaks can only be heard when the vehicle is first started cold. Cast metal exhaust manifolds will expand with heat and seal small leaks from a hair-line crack or gasket failure. Ignore these types of leaks at your own peril, as any leak in the engine bay can easily get sucked into the HVAC fresh-air intake to be delivered directly to your face when behind the wheel.
Don’t forget smells. While carbon monoxide is odorless, the myriad of other chemicals in a vehicle exhaust stream have unique and strong smells. Long before an electronic detector will go off, you might be choking from these fumes.