I would recommend purging the adaptive map only, if all other inspections did not give a clear indication, what might be the reason for an poor engine running.
In most cases there is a reason for a displayed engine check. Deleting the learned adaptive map will not cure the cause of the problem itself.
I did so, after having check nearly all possible causes at my car and being unsure, if the adaptive map trained itself bogus engine constellations.
In the end it resulted first on extremly poor idling & starting and a very lean mixture on one cylinder, which resumed to the original behaviour after having driven a number of hours and passing through all levels of engine load to teach the ECU.
But as the root cause had been a defective ECU which suffered problems on nearly all involved engine sensors and throttled the fuel pressure down to about 40% of the correct level it didn't help at all.
My last joker had been humbling to the next dealer and swapping for investigation purposes the ECU against one of a running car. With this one it run absolutely brilliant again, so it was proven that the ECU was damaged.
This is not a very common failure. ECU's are normally only destroyed by overvoltage problems (shortcircuits, voltage peaks, ...) which normally domnot occur.
My personal suspect is, that S&S had a problem in the manufacturing process of the electronics components (e.g. Oxidized soldering pads, weak soldering, etc.)
I will ask the dealer, if he still has the old ECU and would mind returning it to me, so I could ask my SMD manufacturing experts in our plant to open the decive for a visual inspection. (We are manufacturing automotive electronics since decades)
Last edited by spelunx; 28/09/16 04:42 AM.
