low Z injectors only running in high Z mode

[lt1will620]

so i finally got my twin turbo lt1 up and running on the megasquirt II, but i have one question, im running accell 160lb/hr low Z injectors, but it will only run with the settings , pwm current limit at 75%, correct for low Z, however, when i set the pwm time threshold to 1.0 ms as the MS site says it just fires and then quits, so i went back to the 25 ms setting that was in it, and it runs fine...will this be okay since i am using the current limit setting?

[Bernard Fife]

lt1will620,

If you have the PWM time threshold set to 25.4, then you have no current limiting. The PWM time threshold tells you the amount of time before current limiting starts.

Running without current limiting will eventually damage MegaSquirt, the injectors, or both. What is the DC resistance of your injectors?

Do you have a flyback board on a V2.2 mian board? If so, you need to check the connections, diode orientations, and mica insulators very carefully. Or did you install the PWM flyback damping circuit on a V3 main board (step #69)? If so, you need to check each components, making sure you installed D5 and D7.

Lance.

[lt1will620]

everything is installed correctly, i still havnt measured the resistance, but when i changed the time threshold to 1.5ms and the current limit to 80%, it now runs, but with poor throttle response. these are very large injectors, so maybe it just takes more voltage to keep them open