Consumer Watchdog is not backing down from its bid of calling out Hyundai‘s MPG claims for their popular Elantra, and has now issued out a letter to Hyundai’s CEO asking the company to pull its prominent 40-mpg claims from car’s advertisements until the EPA re-tests the model.

Elantra owners from around the country are reporting that their vehicles’ average gas rating is more in the 18- to 19-mpg range rather than the advertised 29-mpg city, 40-mpg highway that Hyundai is advertising. To add more fuel to the fire, Consumers Union and Motor Trend’s tests were well short of the 33-mpg combined claim and even the most mileage-obsessed drivers over at Fuelly.com couldn’t get their Elantras close to the 33-mpg claim.

And while most people understand that there is a discrepancy between mpg claims from manufacturers and real world driving scenarios, their complaint lies in the fact that the Elantra falls well beyond a 10-percent difference. Consumer Watchdog is now calling Hyundai out as being deceptive and hope that Hyundai will pull the claims from their ads before more consumers purchase the Elantra under false pretenses.

Motor Trend tested the Elantra to 25.9-mpg while Consumers Union averaged 29-mpg. USA Today on the other hand tested just 22-mpg.