We are working on a bmw m54b30 dual vanos n/a engine which has inlet and exhaust cam sensors and inlet and exhaust pwm-ed solenoid vanos.
I have tried to tuning the inlet (vems name it exhaust because of trigger setup) vanos pid but no real good result.
The exhaust refrence position seems ok, this is the balanced position, above it the can start advancing, below retarding.
The most retarded position about 112 deg on third trigger the most advanced about 150 deg. (yes it need between 0 and 4x but we didn't know to find why vems measure this, and this is just a reference so not too important.
When I tried to find the right pid values the step target change was followed well with the cam, but when I wrote an interpolated cam table, then cam can't copy the target.
This is two screenshot show what I want to explain:
This is the whole log file:
http://cosworth.hu/misc/vanos/v3.3_u006652-2013.03.05-18.26.16.vemslogDoes anybody has experience with this?
(Will be good a calc model for all pid in vemstune...which help too solve similar situation)