There's probably different versions of the Ascend G330, depending on the country and where it's intended for sale, e.g. ones for China have the FM transmitter and ones for the United Kingdom do not, due to type approvals and licensing or whatever.
The FM transmitter hardware itself maybe present as part of the device's chip-set, but the actual FM transmitter app is built into the phone's ROM software. And there's different versions of the ROM for different countries and regions. On the other hand non-transmitter versions may not have the transmitter hardware at all. AFAIK there's no separate FM transmitter app you can install, even if the transmitter itself is present but disabled.