Fairuz, a seasoned campaigner in GT racing, started from 18th place after changing his machine class from GT3 to GTM, when his machine, a Lamborghini Gallardo FLII, was badly damaged during the qualifying session Saturday.
The OD Racing Team driver started today's
He finished the race in 40 minutes and 13.778 seconds, 36.101s behind Japan's Naoki Yokomizo from Direction Racing who raced under the same GTM class.
Third place was secured by Frank Yu from the GT3 class who crossed the finishing line in 41:13.790s.
"It was a tough weekend for me and my team. A great rebound from yesterday but driving an unfamiliar car from another category (Super Trofeo) is very challenging but I managed to finish the race.
"The (Lamborghini) Huracan is a much more advanced car but in terms of braking, not as good as my GT3 car," the 32-year-old Fairuz told reporters after the race.
Hong Kong's Michael Choi of Arrows Racing finish third in the GTM class.
Pole sitter, Australia's Josh Hunt of Kurnia AmAssurance Racing had to withdraw from the race due to a system problem with his car.
Meanwhile, another Malaysian driver, Adrian d'Silva of Nexus Infinity secured second place in the GT3 class and was sixth overall in the GT Cup after crossing the chequered flag in 41:26.307s, behind Frank Yu of Hong Kong.
"I started off well in the race, captured the overall second place and was putting in better laps but before facing problems with the gear box.
"I tried to reset the car on the track itself...Later my engineer told me to maintain till the finish line," Adrian said.
Only two drivers raced under the GT3 class after Fairuz changed to GTM class.
The highly anticipated Afiq Ikhwan Yazid was ruled out of the race due to an unsolvable car chassis problem after his car was involved in an accident during the Lamborghini Super Trofeo Series Asia Race 2, Sunday.