Crews recovered one coin that landed inside the engine and eight more in the surrounding area during the inspection, which lasted about five hours.
An elderly Chinese passenger was detained by authorities after she delayed a flight at the Shanghai Pudong International Airport by throwing coins into an airplane engine.
The coins could have been sucked into the engine and caused great damage, even catastrophic failure, said the captain of the China Southern Airlines flight.
She was detained by police following the incident, which forced almost 150 passengers to be evacuated from the flight CZ380 bound for Guangzhou.
Passengers who already boarded the flight were removed as officials attempted to find out if any coins were stuck inside the engine. Police later found nine coins at the site, including one in the engine.
According to Channel News Asia, the elderly woman was traveling with her husband, daughter, and son-in-law. The incident was soon trending on Weibo and police added in a statement: "After investigation the involved passenger surnamed Qiu said she threw the coins to pray for safety".
The flight was eventually given the all-clear and took off at 17:52 local time (09:52 GMT), more than five hours late. "According to Qiu's neighbor, Qiu believes in Buddhism".
China Southern Airlines told reporters that passengers were reminded to comply with civil aviation laws and regulations, which prohibit behaviour that could jeopardise the safety of the flight.