I have a 2014 eco and it’s in the shop at 76000km to have cylinder heads replaced. This is the second set of cylinder heads to go in . This is due to s vibration at about 2000 rpm. I had a chance to look at the motor while it was apart and I noticed two of the middles ports on the intake that bolds on the heads had a lot of wet soot on them . Is this normal. I thought the intake has no liquids going through it , just hot and cold air. I ask the tech about this and he said was nothing to worry about. My mileage ( 12L / 100km) since 10,000 km has been bad and since they couldn’t explain or repair it I now worry about everything thing that seems of. Should worry about this .