Siemens ECUs - the reflash/modding possibilities

[brad black]

I was wondering how the ECU would adjust for changes in fuel/temperature/pressure without closed loop operation.

it adjusts the same way it does in the open loop portion of the map, and the same way every open loop ecu works: the environmental sensors.

as to whether or not something is closed loop or open loop it depends on the model and year.  all siemens ecu are closed loop, std or dp.  as are the Mitsubishi ecu in the mts 1200 and diavel.  the marelli ecu depend on model, only 848 is closed loop in dp from memory.

[metroplex]

I recall the Siemens ECU using both speed density and alpha-n for our Monster. I assumed the speed density portion would be in the closed loop, utilizing the manifold pressure sensor as well as the throttle (alpha) and engine RPM (N), and that it switches to alpha-N in the open loop portion. I can't see the factory calibration to determine if it actually uses the other sensors (air temp, engine temp) to make fuel corrections or whether it is all speed density.

[brad black]

of course it uses the other sensors.

the speed-density at very low throttle openings, or the n-alpha are the base inputs.  the ambient air temp and press and engine temp are applied as trims to the pulse width as defined by the base inputs.

they are n-alpha in the closed loop area as well.

[Raux]

Not trying to be rude
but if you know how to reprogram ecus then why are you asking questions on this level
if you cant reprogram why try to figure this all out