This was a customer request: he arrived with his saucy Beemer loaded up with bits and had been told that fitting a Power Commander plus Autotuner would equal a self-mapping setup. In other words he’d read what it says on the label and believed every word!
Predictably, it didn’t do anything of the sort and had effectively mapped itself to death. The engine was suffering with sooted-up plugs and all sorts… Now Autotuners do serve a purpose, but not for the road – they only work for short bursts followed by a ‘saved’ and uploaded map. Because it takes into account none of the variants (temperature, pressure) it can’t touch a PC set up well on a Dyno.
Anyway, the owner had disconnected the lambdas when he fitted the full Akra’ system and after a conversation prior to his visit the Autotuner was firmly binned. We mapped both cylinders individually and could feel the change in the engine halfway through the job; as we sorted one cylinder and moved onto the other you could feel (and hear) the engine note change as the excess fuel was removed. It gained that crisp BMW ‘crack’ as it sharpened up. Lovely!