High consumption in goal GTI 92

It consumes a lot of fuel, starts failing and pulls black smoke, I put it, control the tempo sensor. Remove the full admission and change all the joints, o'Rings, etc. , Change spark plugs and cables, Revice the pump (good) Control the injectors (good), I did the empty test to the admission pressure sensor incorporated to the ECU and does not generate any change in the march and I have doubts in the operation of the Temp sensor. (DUPLO). A help.

O2 sensor

This car does not carry Lambda probe, if it has a resistor in each injector, what function do they meet? Can the injection pulse increase if they do not work?

Also, I could be the MAF since the coloration of the escape of theáta a rich demacious mescla and that the ECU is not sending correct signals to the injection. As for the resistors, they are usually to decrease the voltages.