Consumption problems

Very good morning, I am new in the forum and I need an help of the experts ..
I have a Japanese 94 corolla to which the engine was changed recently and a 7a -fe 1.8L was installed, which works at one thousand wonders but for some reason the same is consuming me too much, that is to tell me about 15 to 17 to 17 kilometers per gallon, which without being a mechanic I consider that this is very little.
My mechanic takes it where an electrician and he told him that the installation of the sensors is wrong and that this is the problem.
Now the main question is the following the engine is Japanese and as I have investigated this same model it is also American but what I do not know if the computer it brings is the same for both.
Please if someone has the diagram of this engine and that of the computer would appreciate them in the soul ..
greetings and thanks.