The tests were done on different days and the Model Y is further from EPA estimates.
Car and Driver recently got their hands on the all-new Volkswagen ID.4 1st Edition and put it through the publication’s real-world 75-mph highway range test. They compared the results to the results of rival Tesla Model Y, but the tests were done in different temperatures.
The 2021 ID.4 they tested did 190 miles in that test. The EPA’s estimate is 250 miles for combined city and highway driving. That’s roughly 25 percent less, not too bad considering it's a highway-only test. The publication’s testers also measured 82 MPGe on the highway, a little less than the EPA’s 89 MPGe highway estimate.
The ID.4 they used is the rear-drive model with 201 horsepower because that’s currently the only one available in the U.S. It has an 82-kWh battery pack (77-kWh useable). An all-wheel drive version of the ID.4 with about 300 hp will be released in the U.S. later in production.
The Tesla Model Y Long Range Car and Driver tested did 220 miles in the same test and averaged 94 MPGe. It has AWD and an 80.5-kWh battery pack. However, it’s not much of a win for Tesla because its EPA driving range is 326 combined driving and 117 MPGe on the highway. This will make some question the EPA's Model Y estimates. Also, it's important to know that the ID.4 was tested on a 40-degree day and the Model Y on a 75-degree day. Car and Driver states they expect the ID.4 to perform better in warmer weather.
More information on the publication’s 75-mph highway test:
“We run all our tests at a GPS-verified 75 mph on the same 200-mile out-and-back loop on Michigan's I-94 highway. Our consistent procedure includes a methodical fill-up process, following a specific route, using cruise control, and setting the climate control to the same temperature (72 degrees auto). We also correct for odometer error, and we don't test in heavy wind or rain or with extra passengers. In the event we encounter too much traffic or unusual conditions, we abort the run and try again later.”
“We follow the same procedure for electric vehicles and plug-in hybrids, except for these, we have additional steps that include making sure the battery is fully charged before starting and recording the kilowatt-hours (kWh) needed to fill the battery after the drive loop."