In previous entries, I described the oddities with the mechanical efficiency of cylinder No.6 – it was reduced in all load conditions (accordingly, obvious problems with the fuel mixture: it was lean).
I already mentioned that all possible B58 I have diagnosed (and there are more than several) had this oddity. I considered it an inevitable evil/”self-evident” oddity. All of them had it .. till this car.
Unfortunately, the only available information regarding this exact vehicle is: G30/G31 of 2017 (the owner/service wanted to stay completely anonymous), but Rough run data speaks for itself:
Here, in the image from 148th second till 153rd second, we see Overrun – the flywheel adapted correctly.
From 157th to 162nd second – low load (accelerator pedal position: 20 .. 30%). Wait, for this car, not the 6th, but the 1st cylinder is “lazy”!
162nd to 164th second – laziness of the 1st cylinders is stopped. Now all cylinders work correctly!
Here, the cylinder performance by different torques – low and average – all cylinders are performing perfectly! Not a sign of laziness of the 6th cylinder.
What makes this car unique?
Yes, I asked the owner of the car to readapt the engine. It was done.
But before the adaptation, the Integration was restored to S15A-25-03-55. It means – the release of Year 2025, end of March. Now I just have to check – maybe this 6th cylinder laziness will finally be over?
Unfortunately, data (including ISTA live data) regarding this car I have in a limited amount (it was the car of the service customer, who is no longer available in person/after solving the basic problems), so there are more questions than answers.
Laziness (slightly reduced total torque) – that would be half an itty. As I mentioned in the previous entry, there are three more critical issues:
a. cylinder No.6 (obviously) works in a lean fuel mode, it can “catch” knocking faster;
b. due to the leaner average fuel mixture, there is a larger possibility of “catch” misfires;
c. Due to the incorrect individual fuel mixture of the cylinders, the CO catalytic converter is overloaded and damaged prematurely.
