[urq] Hesitation, bucking on takeoff - not yet resolved!

[urq]

... we need to be careful about nomenclature here ...
 
The urq has only one "Hall sensor" ... it is on the distributor.  The flywheel sensors are not Hall-effect devices (i.e. semiconductors), they are called variable reluctance sensors.  These basically capture the moving magnetic field from a piece of ferrous metal and turn it into an electrical signal.  There are two such sensors on the bellhousing, one is positioned in a way that creates an electrical signal as each and every flywheel tooth passes by and the other senses a metal pin that is installed in the flywheel, which indicates the absolute position of the flywheel.  
 
As I said in my earlier post, the ECU depends on all three of these signals to control the operation of the engine.  If any one of them fails the engine is not likely to be able to run.  I admit that there may be situations where the car might be able to continue to run if a sensor fails after the engine has started (that one being the Hall sender).
 
Steve B
San Jose, CA (USA)
 
==========

I confirmed this during my cutout issues. The car will die with a loss of the distributor hall, or the "run" hall (mounted on the tranny bell housing). Once running, the "start" hall (on the engine block near the head) can be unplugged and the ECU doesn't care....until you stop and try to restart that is.