Stock fuel injection / 034 EFI

Marc Swanson mswanson at mswanson.com
Wed Jun 12 23:19:45 EDT 2002


> The URQ uses ignition timing at idle to control the speed, how is this done
> ?

exactly as you say.. when it adjusts the timing it can change the A/F ratio
by changing at what point before or after TDC it fires the plugs.  This can
be used in the same manner as adding air through an auxilliary valve.
Obviously there needs to be enough air available with the throttle plate
closed as well (so the UrQ must either get enough air through the idle screw
or has some other pathway of air that bypasses the TB).


> Also could you use a small air solenoid to pass extra air when needed and
> have it activated by some means when needed.....integrating ignition
> pulses, monitoring battery voltage, simple switch activated along with high
> current device that drags the idle down etc.
> Integrating the ignition pulses would work best I feel. Use a diode to
> rectify and charge a cap on the base of a PNP transistor, voltage too low
> and the transistor will switch on and control the valve ????


yes, certainly.  I don't have the time or drive  to design such a device at
this point however, and the fuel ECU already receives all the necessary
inputs to do just that... and a software interface as well.  Besides I
wouldn't want to have to change out a few capacitors just to change my idle
speed ;-) (yes I know, you could probably design it with a few trimpots to do
the same thing but that is beside the point).


-Marc-
87 4ktq
88 90q



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