The trial is designed to ensure all new machines are working at capacity and the engines produced meet the quality standards Toyota is renowned for.
It also provides production, maintenance and logistics employees the opportunity to develop new skills relating to hybrid technology and standardise work practices before the plant goes into full production.
Chris Harrod, Toyota Australia's executive director of manufacturing, said the trial build was an important milestone for the company.
"The success of the first trial means we are one step closer to going into full production," Mr Harrod said.
"The new engine plant is an Australian first for producing both petrol and hybrid engines. In fact, it is the first simple slimline engine plant to be built outside of Japan and reaffirms our position as a leading manufacturer.
"Once we commence full production, the new plant will produce engines for our locally manufactured cars - Camry and Camry Hybrid - and open up new export markets in Thailand and Malaysia."
Mr Harrod said the engine plant also has a unique set-up with casting, assembly and machinery all housed under the same roof to improve efficiencies.
The new plant is located at the Altona manufacturing plant in Melbourne and has been in development since October last year. It will replace the previous engine plant that was built in 1978.
The plant is expected to commence volume production at the end of the year and will produce approximately 450 engines per day.
Thirty four-cylinder engines were produced during the two-week trial.
The total investment in the new plant is around $330 million and was secured by Toyota Australia with co-investment from the Victorian Government and $63 million from the Federal Government's Green Car Innovation Fund.
Toyota employs a total of 4200 people in Australia.