Running Rich 2

I have the same problem!

Ever since I have gotten my skyline r33 gts25t serviced and tuned it seems to be running rich - (lots of black sotty stuff in exhaust and prevalent smell of unburned fuel after turning car off).

Before service and tune was getting 480 to 530ks (11/12 litres per 100kms)from 65 litre tank- now getting about 380ks (16/18ltrs per 100kms) per tank driving same way (alot of time off boost). Is this normal? What is normal mileage for my car? Is this because running rich? If so what can be done to fix problem???

Can the air fuel mixture be adjusted and if so how???
Could it be faulty Airflow meter or O2 sensor?
Please help!

I don't know what they did, but you can get a fuel flow regulator. Just a reminder running lean will created detonation. Not good. If you get one, it is better to run a little rich than running a little too lean.

THe first things I'd check would be your O2 sensors. If they go out or start going out, they will probly read Lean and your ECU will say to dump fuel. Also, just for shits and Giggles, try resetting your ECU.

Lemme know how that goes.