Thermal Sensor and Load Sensor

[Mike Fahrion]

>waht about a hall effect sensor on the flywheel teeth,  with
the numebr
>of teeth an ECM would be able to \detect misfires by measureing
angular
>velocity changes, and to correct accordingly.    I wonder if
that would
>work as a detonatiom detection.  Has anyone tried sampling
>velocity/accelleration of the crank at the flywheel during
detonation??
>might be a simpler way than using a knock sensor to see
detonation. ( i.e
>rapid change in angular velocity, due to bad power stroke(s),
plus easily
>adaptable to ANY engine..
>
>Dave


This is how obdii cars monitor misfire and it seems to work
remarkabley well for that (considering that it is very complex).
They still have seperate (traditional) detonation sensors
though, perhaps they don't trust the data enough for the
critical detonation detection?

One snag with the angular velocity scheme is that a bumpy road
tends to set it off. One mfg had to discontinue the standard
transmission in their US-destined cars.  Cars with automatics
usually unlock the TCC when an angular velocity disturbance is
found in order to isolate the crank from the road. Others use
ABS sensors to detect rough roads.  On second thought, these
reasons would make knock detection difficult using crank
velocity.

-mike
mfahrion at bb-elec.com