clarification of MS1 Extra Tuning Manual

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07-13-2013, 10:55 PM

mx594m

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clarification of MS1 Extra Tuning Manual

the manual says....

Setting the PWM Criteria

To tune the PWM [pulse width modulation] values for your engine, you need to know what kind of injectors you have: low impedance or high impedance.

If you are running high-impedance injectors (greater than 10 Ohms), then set the:
PWM Time Threshold to 25.4 msec, and the
PWM Current Limit (%) to 100%.

In essence you are disabling the PWM mode. This allows full voltage to the injectors throughout the pulse widths.

I am using Delphi 525 EV6 injectors, these measure 12 ohms; therefore they are high impedance injectors.

If I set my PWM current limit to 100% and my PWM time threshold to 25.4 msec then I effectively disable PWM mode and cannot use it for idle control?

Is this correct, I cannot use PWM for idle control when using high impedence injectors?

07-13-2013, 11:30 PM

hornetball

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The PWM or DC (Duty Cycle) we use for idle control is a signal to the idle air control valve (i.e, the air leak). The fuel injectors work the same way at idle as they do everywhere else on the VE map. Basically, Req. Fuel x VE x Gains = Injector Pulse Width (at full vultage for high-impedance injectors).

So, relax . . . it'll work.

07-13-2013, 11:53 PM