A coastdown test is a procedure that determines key metrics used to calculate a vehicle’s fuel consumption values or “L/100kms rating.” The litres per 100kms ratings are established using a machine called a “dynamometer.” A dynamometer is like a treadmill for vehicles, enabling vehicles to be operated indoors on a stationary platform to simulate real-world vehicle operation. The level of resistance on the dynamometer is adjusted for each specific vehicle model tested to simulate the level of resistance that the vehicle would encounter if operated outside on the road. Coastdown testing is used to determine the appropriate resistance levels (or “road loads”) to use on the dynamometer for a given vehicle model. Coastdown testing is used to measure all types of resistance encountered by a given vehicle model during real-world operation, including:
HYUNDAI/KIA FUEL CONSUMPTION BACKGROUND
Fuel consumption is measured under controlled conditions in a laboratory, using a device called a dynamometer. The dynamometer simulates a vehicle driving on the road. Fuel consumption is measured by determining how much of certain gases are emitted from the vehicle during the test cycle. Emissions are measured to determine how much fuel is burned and then converted into litres per 100kms for the fuel consumption label. The same measurements are now used for purposes of the Environmental Protection Agency’s and Environment Canada’s greenhouse gas program.
All manufacturers test prototype vehicles, calculate the fuel consumption information and submit the data to the EPA for review. EPA issues Certificates of Conformity based on the data submitted by manufacturers. Environment Canada accepts EPA Certificates of Conformity as evidence the vehicle meets Canadian emissions regulations. Confirmatory tests are run on a percentage of production vehicles. There are typically variances between the prototype test information originally submitted to EPA and Environment Canada and the later production tests.
In order to measure and calculate fuel consumption, a manufacturer must first assess each vehicle’s “coastdown” value. This value is determined through a series of tests run by the manufacturer. The EPA informed Hyundai and Kia’s technical center that it had questions about how Hyundai and Kia had determined the coastdown values for its vehicles. EPA’s independent testing had resulted in coastdown values different than those reported by Hyundai and Kia.
Hyundai/Kia Cooperative Test Program with EPA
The companies engaged in a testing program with EPA to determine the source of the test result differences. The companies’ technical team found certain discrepancies in the way in which the coastdown testing was conducted. EPA also found that the companies’ interpretation of certain aspects of the procedures differed from EPA’s understanding of how the tests are generally conducted.
Hyundai/Kia Future Testing
Hyundai and Kia have agreed to conduct all future testing in the manner EPA has communicated to the companies and to rectify certain procedural errors found during the test program. The procedural errors relate primarily to how the companies’ testing engineers identified vehicle weight and chose test runs for calculation of the coastdown values. Hyundai and Kia are committed to working with EPA to ensure that all future testing meets EPA’s expectations.
FUEL CONSUMPTION RATINGS BACKGROUND
Fuel Consumption Ratings
Fuel consumption is measured under controlled conditions in a laboratory, using a set of tests that are set forth in regulations issued by the U.S. Environmental Protection Agency (EPA) and adopted by Natural Resources Canada (NRCan). The test results are used for two purposes: (1) to establish compliance with the greenhouse gas emissions regulations; and (2) to provide the estimated fuel economy rating for each vehicle. These ratings are applied to fuel consumption labels normally found on showroom new vehicle windows and are published on the Canadian government-sponsored website: http://oee.nrcan.gc.ca/transportation/tools/fuelratings/ratings-search.cfm
Fuel Consumption Labels and Real World Performance
Both EPA and NRCan websites advise that while its ratings are a useful tool for comparing the fuel economies of different vehicles, fuel consumption ratings are not fixed numbers. According to NRCan, “…no test can simulate all the possible combinations of climate road conditions, vehicle load and driving habits. As such, your vehicle’s fuel consumption may differ from the estimates…” EPA and NRCan have identified several factors that can lower a car’s fuel consumption including: cold weather, aggressive driving, excessive idling, accelerating, and braking in stop-and-go traffic, driving with a heavy load or with the air conditioner on, improperly tuned engine or under-inflated tires; use of remote starters, and small manufacturing variations.
More information on fuel consumption labels and real world performance can be found here: http://www.tc.gc.ca/eng/programs/environment-fcp-faq-139.htm
HYUNDAI FUEL CONSUMPTION REIMBURSEMENT PROGRAM FACTS
Hyundai is committed to fully reimbursing affected current and former vehicle owners for the difference in fuel costs associated with our rating change. Our top priority is to make things right for Hyundai owners.
Applicable Time Period Limitations
HACC Processing: Hyundai will review owner requests and send reimbursement within 30 days of their complete claim submission.