Although cars run cleaner than ever, a phenomenon with direct-injection systems makes it not always appear that way.
In the past, a black tailpipe in a gasoline-powered car meant one thing: a fuel mix that was too rich, or sub-stoichiometric, causing unburned hydrocarbons to coat the inside of the tailpipe. Today’s engines run three-way catalysts to scrub any unburned hydrocarbons that escape the various other emission-control systems, leaving very few to darken our tailpipes.
And yet, many modern tailpipes are blackened. According to John Hoard, an associate research scientist in the mechanical engineering department at the University of Michigan, gasoline direct-injection engines, like diesel engines, have a tendency to produce particulate matter, also known as soot.
Modern diesel engines have particulate filters to counter soot production. Diesel particulate filters occasionally run a regeneration mode in which the exhaust temperature is increased and the trapped soot burns off, reducing filter pressure. In most cars this happens in the background without the driver having any knowledge of its occurrence, though owners of modern diesel vehicles know when this happens as fuel economy drops precipitously.
This content is imported from OpenWeb. You may be able to find the same content in another format, or you may be able to find more information, at their web site.
Ireland Latest News, Ireland Headlines
Similar News:You can also read news stories similar to this one that we have collected from other news sources.
Jay Leno Is Bound To Love The Volvo P1800 Cyan, Right? | CarscoopsThe Volvo P1800 built by Cyan Racing is much more simple than most modern sports cars
Read more »
Downpours left basements, streets flooded all over North and Northwest sides, and some say it's a recurring problemCBS 2's Chris Tye explored where the storms hit, the calls for service, and why certain neighborhoods get hit the hardest most often.
Read more »
Toyota Built a Handful of GR86s With Turbo GR Corolla EnginesThey're testbeds for future race cars and synthetic fuels, not production cars.
Read more »
Shiseido @ 150: The Trailblazer.SHISEIDO_corp, the oldest continuously operating cosmetics company is also one of beauty's most modern.
Read more »
‘Best little guy’: Octogenarian offers vehicle inspections, inspiration on the South SideAt John’s Inspection Station on South Flores, customers often get more than their...
Read more »