SACRAMENTO – The California Air Resources Board Wednesday announced a settlement with Fiat Powertrain Technologies Industrial S.p.A for emissions-related violations affecting nearly 2,000 on-road and off-road diesel engines.

The settlement includes a mandatory recall of affected vehicles and $6.4 million in penalties.

The enforcement case began after the company informed CARB in 2015 that it had made unapproved repairs and modifications to CARB-certified on-road engines. The repairs, commonly called “field fixes” because they are made after the vehicles have been sold, were intended to address an oil leakage problem in 2011-2014 model-year engines.

Emission-related field fixes must be reviewed and approved by CARB to ensure they don’t increase emissions. Fiat failed to inform CARB about the fixes when they were made and also disclosed that it had certified 2014-2016 model year off-road engines using incorrect emissions data. Fiat fully cooperated with CARB’s investigation.

“It is illegal for manufacturers to perform emission-related repairs and modifications on their engines or vehicles without first submitting the proposed repairs to CARB for approval,” said CARB’s head of enforcement Todd Sax. “These illegal modifications may increase emissions of toxic and smog-forming pollution both on and off our roads and highways. That is a particularly serious concern in California where 12 million people live in areas with the worst air in the nation.”

As part of its settlement with CARB, Fiat must implement a full, mandatory recall of vehicles equipped with the on-road engines in order to correct the oil leakage issues and provide a one-year warranty for the replaced parts. Fiat must also conduct additional in-use and on-board diagnostic testing on several repaired vehicles containing these engines.

The company will pay $2 million of its $6.4 million penalty to a Supplemental Environmental Project to install air filtration systems in facilities with sensitive populations, such as schools, senior centers, and hospitals throughout the Bay Area. That program is administered by the Bay Area Air Quality Management District.

The remaining $4.4 million will be paid to the Air Pollution Control Fund to support air pollution research and education.

Diesel exhaust contains a variety of harmful gases and more than 40 other known cancer-causing compounds. In 1998, California identified diesel particulate matter as a toxic air contaminant based on its potential to cause cancer, premature death and other health problems.