An earlier version of this story had inaccurate information on Ford’s stock. This story has been corrected.

Ford Motor Co. revealed an internal investigation on Thursday into whether its vehicles have worse gas mileage and emit more pollutants than car, truck and SUV labels reveal — going back to 2017 models.

An anonymous “Speak Up” reporting system at Ford raised the issue in September 2018, the company said.

Ford said Thursday it had hired an outside team to evaluate whether Ford’s mathematical model was flawed in how it determined miles per gallon and emissions ratings.

To begin the review, Ford said, it will start testing the wildly popular new 2019 Ranger midsize pickup, which just went on sale. And then other models would be tested.

The Ranger was recalled on Feb. 6 for faulty wiring that can prevent the pickup from shifting properly and parking safely.

Ford officials emphasized that the fuel and emissions ratings inquiry is in its preliminary stages and nothing points to a problem at this time.

The company sold nearly 2.6 million Ford and Lincoln vehicles in 2017 and nearly 2.5 million vehicles in 2018, according to financial filings.

Ford spokesman Said Deep said: "As soon as we learned of our employee concerns in September, we engaged a third party firm at the end of October to perform initial review, which ended in December. We began a full internal investigation in December, leading to this week's voluntary disclosure about our investigation to the EPA and CARB. We estimate the full investigation will take several more months."

Ford said in its Thursday news release that the company alerted California regulators, who are exceptionally strict about pollution oversight in one of the biggest car markets in the world.

But Dave Clegern, spokesman for the California Air Resources Board (CARB), told the Free Press later Thursday that “as of this moment, CARB has not received notification of the mileage issue from Ford.”

Early Friday, Steve Cliff, deputy executive officer of the California regulatory agency, told the Free Press, “We learned of apparent concerns with Ford’s emissions certification through reports in the press. Rest assured we’ll be carefully scrutinizing this issue in discussions with the automaker. CARB takes seriously violations of our regulations, especially given the recent high profile cases such as Volkswagen."

Deep responded on Friday, "We spoke to Mary Nichols, head of CARB, yesterday at 4:15 California time," which is three hours earlier than Michigan.

He confirmed the call was made by Kim Pittel, group vice president for sustainability, environment and safety engineering at Ford.

Ford released its news advisory at 4:30 p.m. Michigan time.

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Michael Abboud, EPA spokesman, confirmed to the Free Press that Ford reached out to the EPA a few days before releasing the public statement.

“On Feb. 18, 2019, Ford disclosed to the U.S. EPA that it had discovered potential issues in its emissions certification processes,” Abboud said. “On Feb. 20, 2019, Ford briefed the agency on the information it has developed so far in the investigation. The investigation is ongoing and the information too incomplete for EPA to reach any conclusions. We take the potential issues seriously and are following up with the company to fully understand the circumstances behind this disclosure.”

Late Thursday, Safe Climate Campaign, Public Citizen and the Sierra Club released a statement through the Sierra Club: “It’s shameful that Ford waited months to disclose issues with its emissions testing."

Karl Brauer, executive publisher at Kelley Blue Book, praised Ford for being proactive and informing the public.

“I think it’s really smart for Ford to get in front of this circumstance,” he said. “Clearly, they discovered something that may suggest an inaccuracy in how they’re defining and determining their fuel economy for their cars. They started to dig into it and wanted to get a handle on the issue before they said anything. Now they’re letting everybody know.”

Ford deserves recognition for having a program that allows tips for potential problems, Brauer said.

Pittel, who is handling this matter for Ford, said in a prepared statement, “In September, a handful of employees raised a concern through our Speak Up employee reporting channel regarding the analytical modeling that is part of our U.S. fuel economy and emissions compliance process."

Ford officials said they believe trust in the brand "is earned by acting with integrity and transparency."

Pittel outlined actions to include:

Hiring an outside firm to conduct an investigation into the vehicle road load specifications used in testing and applications to certify emissions and fuel economy. Road load is a vehicle-specific resistance level used in vehicle dynamometer testing, including for fuel economy ratings and emissions certifications. Road load is established through engineering models that are validated through vehicle testing, including physical track tests referred to as coastdown testing.

Hiring independent industry technical experts as part of Ford's investigation team.

Hiring an independent lab to conduct further coastdown testing.

Evaluating potential changes to Ford's road-load modeling process, including engineering, technical and governance components.

Voluntarily sharing this week potential concerns with Environmental Protection Agency and California (California) Air Resources Board officials.

“At this time, there’s been no determination that this affects Ford’s fuel economy labels or emissions certifications,” Pittel said. “We plan to work with regulators and the independent lab to complete a technical review. As part of our review, we have identified potential concerns with how we calculate road load. The first vehicle we are evaluating is the 2019 Ranger; we are assessing additional vehicles as well.”

Labeling issues in 2014

This latest labeling issue is not the first for Ford, which sent checks to 215,000 Ford and Lincoln owners in June 2014 after they purchased vehicles with inaccurate fuel economy ratings. Models included the 2014 Ford Fiesta as well as hybrid version of the 2013-14 Ford Fusion, C-Max and Lincoln MKZ and the C-Max Energi plug-in hybrid.

At that time, ratings were off by 1 to 7 mpg. Reimbursement depended on whether the vehicles were leased or purchased. Checks varied from $124 for a leased Fiesta to $1,050 for a purchased Lincoln MKZ.

Raj Nair, then-head of Ford’s global product development, said a discrepancy in testing was detected in October 2013 and subsequent testing traced the problem to a new process for correlating wind tunnel results. Those figures are used to determine the resistance level set on the dynamometer that tests vehicle mileage.

After the incident, Ford agreed to enhanced validation tests for future vehicles under EPA oversight to prevent the error from occurring again.

News reports in 2014 noted that it was the second time in a year that Ford had to lower mileage figures on some models. In 2013, Ford voluntarily lowered its claim for the C-Max hybrid from 47 to 43 mpg after Ford tested the Fusion hybrid and applied the same numbers to the other vehicle.

2019 FCA emissions settlement

Accurate labeling has been an issue for other automakers, too.

Fiat Chrysler Automobiles settled a case with the U.S. Justice Department in January 2019 in response to diesel emissions irregularities and allegedly hiding attempts to deceive regulators. As a result, affected vehicle owners received cash payments of more than $3,000 each.

Including about $400 million in civil penalties, an extended warranty, a proposed class-action legal settlement and other costs, FCA is expected to spend more than $790 million to resolve cheating allegations involving approximately 100,000 2014-16 Eco-diesel Ram 1500 pickups and Jeep Grand Cherokees.

While FCA declined to admit wrongdoing, Volkswagen confessed to cheating on U.S. diesel emissions tests. Both companies were accused of installing software known as "defeat devices," which allowed vehicles to pollute more on roads than during testing.

Ford explicitly noted Thursday that no defeat devices were used.

Contact Phoebe Wall Howard: phoward@freepress.com or 313-222-6512.Follow her on Twitter @phoebesaid