It's a 2005 Toyota camry, for a couple of months now the fuel consumption rate has increased drastically. What could be the likely cause. Please i need ur responses my competent gurus. Thanks house.

A lot of things can be responsible. O2 sensors, injectors. Ecs, Tyre size, Tyre psi, bad thermostat or absence of thermostat, engine running rich due to spark plugs, coils, engine temperature not getting to operating temperature because fans have been connected directly and thermostat removed; catalytic converter, etc etc.

What engine size do u have and what mpg are u getting? Do u have a check engine light on, have u scanned the car?

Au much does car scanning cost?

abatically:
A lot of things can be responsible. O2 sensors, injectors. Ecs, Tyre size, Tyre psi, bad thermostat or absence of thermostat, engine running rich due to spark plugs, coils, engine temperature not getting to operating temperature because fans have been connected directly and thermostat removed; catalytic converter, etc etc.

What engine size do u have and what mpg are u getting? Do u have a check engine light on, have u scanned the car?

In addition to this oga;
vacuum leak, weak fuel pump, bad fuel pressure regulator, dirty fuel/air filter, faulty knock sensor, exhaust leak, new tires(high rolling resistance), improperly aligned/unbalanced tires, faulty coolant temperature sensor, high engine oil viscousity/overguage, high transmission fluid viscousity/overguage, low octane fuel(especially when knock sensor is faulty), unbalanced injectors, wrong spark plugs, sluggish/bad A/F / O2 sensor, faulty throttle position sensor, wrong ignition timing, valve faults, intake manifold crack, malfunctioning egr, malfunctioning pcv, misaligned pulleys, inadequate d.c battery voltage/corroded or aged electrical connections, clogged exhaust/gutted cat, transmission faults(stucking in lower gears for too long), bad ignition cables/weak ignition coils, driving style(harsh driving), faulty MAF/MAP sensor, bad roads. e still remain o..... I no remember others now.
note: some of the above mentioned do not cause drastic rise in fuel consumption.
Regards....