Since having the scoobysport box and a ramair filter(which may i say give a lot more smiles per mile)i have noticed that there is always a sooty deposit on the inside and on the rolled lip of the tailpipe.Does the ECU automatically adjust the fuelling or does it sound like i need to have the mixture adjusted?.Also is it better to have my dealer do it or are better results achieved at a rolling road?.

 

TC, The ECU alters the mixture settings automaticly. Brief Tecnical spiel; The oxygen sensor monitors the exhaust gases and tells the ECU if the engine is running lean or rich and adjusts the settings as required (I think!!) I don't think it is possible to manually adjust the settings.

 

All turbo Impreza's seem to suffer from sooty exhausts . It's quite normal and nothing to worry about.

 

The ECU overfuels to protect the engine.