Injector Pulse Time Schematic Wanted and O2 Meter comments

[David Hoerl]

I recently built the O2 Meter shown in the Projects page. This has been
of enormous help in understanding what my BMW Motronics system is up to.

However, I find I'd also like to know what is going on in terms of injector
pulses under different circumstances. I know there are some commercial
LED meters that show low to high injector pulsing. Does anyone have a 
schematic for such a thing?

If its on the 'net somewhere, please let me know by direct email. 

I highly recommend building that O2 meter! I went to Radio Shack and got a
small black box with a circuit card inside for about $2, then bought a
cigarette lighter plug which I used to get power. On the signal side
(going to the O2 sensor) I put two spade lugs (on male, one female), then
ran two wires from inside the car to my O2 sensor location, also with two 
spade lugs (m&f). (Note - I have the one wire O2 sensor). By attaching
the O2 sensor and its ECU wire to the wires going into my passenger
compartment, I can now easily connect both spade lugs to the O2 meter 
and see what the ECU does during closed loop (ie, O2 sensor connected to the
ECU and to the meter) and open loop performance (O2 sensor just connected
to the meter, the ECU open circuit, in which case the ECU biases the line to
stochiometric 0.6 volts, and basically provides standard, unmodified
settings.

David Hoerl
dfh at ariel.com