One of the biggest winter myths is that the engine needs to be warmed up for several minutes before being driven first thing in the morning. Twenty-five years ago this may have been true. Today, idling is not only a complete waste of money, but it also pumps needless emissions into the atmosphere.
Until the engine and catalytic converter are fully warmed up, the vehicle is producing peak emissions. The best way to get things warmed up is to drive the car. As such, idling a modern car for more than 30 seconds is too long, even in the dead of winter. Reducing the morning idle time from five minutes to 30 seconds saves 1, on average, 66-litres of gasoline a year.2 And that’s sitting in the driveway going nowhere!
For those living in extremely cold areas, the use of a block heater connected to a timer is advisable. In a test program conducted by Environment Canada, a vehicle sitting at -25°C was warmed using a block heater and then driven over a simulated urban driving cycle. This resulted in a 25% reduction in fuel consumption compared to cold-starting the vehicle and driving it over the same route. 2
One of the false arguments made to justify idling is that it costs money to shut the engine down. In reality, ten seconds of idling consumes the same amount of fuel as starting the engine after shutting it down. As for the wear and tear factor on the battery and starter, it adds up to about $10 per year, which pales in comparison to the cost of idling. 3
Prolonged idling is also one of the worst things the owner can do to an engine. Excessive idling can contaminate the engine oil, which will lead to premature, and very costly, engine wear down the road. It also allows excess moisture into the exhaust system, which promotes corrosion and premature replacement.
The practice of idling with a low fuel level not only stirs up any dirt in the tank, but it also promotes the build-up of condensation in the tank, especially in colder temperatures. Keeping the tank topped up minimizes both risks. When the temperature plummets, any moisture in the fuel system will freeze. If this happens in the fuel line, the car will not start and must be thawed in a warm garage before it will restart.
A recent Canadian survey conducted by Leger Marketing found that 85% of mechanics agreed that the top benefit of using high quality gasoline is optimized engine performance. “Carbon deposit build-up or “engine gunk” on critical engine parts is the result of various chemical and physical processes that occur in the engine during its normal operation,” explains Jim Macias, a fuels technology manager at Shell. “With 20% more cleaning agents than before, Shell Nitrogen Enriched Gasolines protect intake valves and fuel injectors from performance-robbing gunk while you drive.”
This winter keep idling to a minimum to keep things ticking along smoothly by keeping your engine protected!
Source 1: Consumer Energy Center: http://www.consumerenergycenter.org/myths/idling.html
Source 2: Natural Resources Canada: http://oee.nrcan.gc.ca/transportation/idling/14743
Source 3: Natural Resources Canada: http://oee.nrcan.gc.ca/transportation/tools/calculators/Idling/idlingimpact-individual.cfm
(NC) Graeme Fletcher is a licensed mechanic and automotive journalist working for Shell.