Port Authority Police are looking into the second of two vehicles stolen from the airport on Sunday.
Officials said in the latest incident, police are looking for a white Mitsubishi SUV with a reported PA license plate number "LCW4115" stolen from the airport before 7:20 p.m.
Police say the owner left the car running near one of the terminals and a thief jumped in and drove off.
On Sunday, police reported another incident where a vehicle left running was stolen at EWR.
Port authorities police are reminding drivers who drop off passengers at the airport never to leave vehicles unattended and running as potential thieves look for accessible opportunities.
Both incidents are under investigation.