Originally Posted By: vincegt
Definitely runs rich; the tailpipes are sooty inside. I have concerns for the longevity of the engine because of that. Combine EGR and DI, and your valves can build up gunk prtty quickly (no gasoline detergent to clean them). We'll see.
While not a Skyactiv motor, the DI turbo I4 in my Mazdaspeed 3 runs very rich at high throttle openings. The back of the car is peppered with soot after a three day HPDE. That said, the motor is running strong with no issues after nearly 151,000 miles.