Police and state officials responded to the vehicle located along the 310 block of North Washington Street just after 3 p.m.
The entire area was evacuated as bomb experts worked to remove the potentially unstable explosives from the car, officials said.
A large staging area was set up about a block from the scene. Firefighters, EMS and police vehicles escorted a bomb squad truck containing the potential explosives several miles from the scene to a deserted field, where they detonated the device just after 7 p.m., officials said.
The device may be related to a drug operation, which was previously run out of a home along the same block, according to sources. Almost $200,000 worth of marijuana was confiscated from a home back on May 13.
Authorities are investigating the incident.