L-Jetronic peculiarity

[James Montebello]

>  The L-Jet has a spark signal from the distributor to get 
> RPM, but it's not timed to the crank at all, so perhaps Bosch just 
> drives the injectors at some frequency high enough to make sure no 
> cylinder goes too long without an injection event.

Actually, I think Bosch's experience with CIS showed them that 
simply running the injectors continuously, only varying the 
flow rate with load, was "good enough".  At least it was for
US emissions regs up to around 1990.  It's a simple control
strategy, easy to do with all mechanical or electro-mechanical
systems.  Now that sufficiently fast digital hardware is so 
cheap, they can return to the more complicated strategy such
as the one they employed in the D-Jet system, and do all the
hard stuff in software.

james montebello