I have a 2015 Mazda CX-5 with the Skyactiv-D 2.2 liter diesel engine. The car consumes a lot of diesel, 0,9-1 liter per 10 km or 23-26 MPG.
I initially thought that the problem was due to the infamous problem these engines have with the EGR recirculation into the intake manifold building carbon deposits and starving the engine of air, so I had the car dropped off at a shop to have the intake manifold and intake ports cleaned. The shop also say that they cleaned the EGR valve. I saw before and after pictures of the cleaning and it was very much needed. This made the consumption go down slightly but it's still very high.
The strange part is that the car consumes a lot of fuel by just minor acceleration or load. Cruising at medium speed, 70 kmh / 40 mph, makes it the most efficient, almost down to what the car is supposed to consume but not quite there, but highway speed is the worst for it by a large margin. It seems any load at all makes it consume a lot of fuel.
The car works alright, no difficulty starting it, runs fine and accelerates fine. The only problem is that it seems to lose some power at very high revs close to redline, which means that if you accelerates with kickdown it does take some time to pass the threshold before it goes into next gear on high rev.
Today I warmed it up and took it for a spin with the OBD reader to check some values. Here are the values:
Mass Air Flow Rate: 1,5 to 3 g/s at idle, 22,8 g/s at 3000 rpm, 44,6 g/s at kickdown. What is this value? Is this a calculated value?
Mass Air Flow Sensor A: 6 to 12 g/s at idle, 90 g/s at 3000 rpm, 178,9 g/s at kickdown. Should be OK?
Manifold Air Pressure: 1 to 1,5 psi at idle, 2,8 psi at 3000 rpm, 3,6 psi at kickdown. This sounds extremely low.
Exhaust Pressure Bank 1: 15,6 to 16,7 psi at idle, 50,6 psi at 3000 rpm, 64,1 psi at kickdown. This also sounds high? DPF problems?
Vacuum: -23,6 to -26,6 in/hg at idle, -21 in/hg at kickdown. Maybe it's never supposed to be positive on a diesel?
Commanded Boost Pressure A: 9,2 psi at idle, 36,6 psi at kickdown.
Boost Pressure Sensor A: 9,3 to 14,5 psi at idle, 37,4 psi at kickdown. Turbo values seems alright.
Can anyone help shed some light on what might be wrong with it?
I initially thought that the problem was due to the infamous problem these engines have with the EGR recirculation into the intake manifold building carbon deposits and starving the engine of air, so I had the car dropped off at a shop to have the intake manifold and intake ports cleaned. The shop also say that they cleaned the EGR valve. I saw before and after pictures of the cleaning and it was very much needed. This made the consumption go down slightly but it's still very high.
The strange part is that the car consumes a lot of fuel by just minor acceleration or load. Cruising at medium speed, 70 kmh / 40 mph, makes it the most efficient, almost down to what the car is supposed to consume but not quite there, but highway speed is the worst for it by a large margin. It seems any load at all makes it consume a lot of fuel.
The car works alright, no difficulty starting it, runs fine and accelerates fine. The only problem is that it seems to lose some power at very high revs close to redline, which means that if you accelerates with kickdown it does take some time to pass the threshold before it goes into next gear on high rev.
Today I warmed it up and took it for a spin with the OBD reader to check some values. Here are the values:
Mass Air Flow Rate: 1,5 to 3 g/s at idle, 22,8 g/s at 3000 rpm, 44,6 g/s at kickdown. What is this value? Is this a calculated value?
Mass Air Flow Sensor A: 6 to 12 g/s at idle, 90 g/s at 3000 rpm, 178,9 g/s at kickdown. Should be OK?
Manifold Air Pressure: 1 to 1,5 psi at idle, 2,8 psi at 3000 rpm, 3,6 psi at kickdown. This sounds extremely low.
Exhaust Pressure Bank 1: 15,6 to 16,7 psi at idle, 50,6 psi at 3000 rpm, 64,1 psi at kickdown. This also sounds high? DPF problems?
Vacuum: -23,6 to -26,6 in/hg at idle, -21 in/hg at kickdown. Maybe it's never supposed to be positive on a diesel?
Commanded Boost Pressure A: 9,2 psi at idle, 36,6 psi at kickdown.
Boost Pressure Sensor A: 9,3 to 14,5 psi at idle, 37,4 psi at kickdown. Turbo values seems alright.
Can anyone help shed some light on what might be wrong with it?
