I just put together a 5.3 turbo on microsquirt and I'm having an issue with it running. It will fire up and idle (2000rpm) but every 5 seconds or so it has a flat spot in the duty cycle and it drops to 0 for a split second then it goes back up to normal, then again.

Any ideas where to start to track down why I would have an intermitten signal issue with injectors?

 

Monitor battery voltage and see if it is jumping around. If so its likely a loose ground. Also use the tooth logger to verify solid crank position sensor output. O'reiley crank POSN sensors are prone to intermittent failures.

 

looking into that now. Also, do all sensors need to be physically grounded? I'm only getting continuity to ground from the two pins (grounds) for the microsquirt

 

Make sure sensors are grounded as shown here. Crank posn can be grounded to main Micro ground. I don't recommend sing the sensor GND for it.

http://www.useasydocs.com/details/ew3_hires.gif

 

Ok i've redone the sensor ground (it had a bad cold solder connection). I am not sure if the Crank sensor ground is separate or if it its used in the sensor ground. Why do you recommend not using it in the sensor ground?

 

IT's not having any drops in pulse width now that I can see.. idles better but still bounces between 1400 - 800 rpm

 

Call me.

Chk your pm for my phone number

 

Got it, i'll buzz you this afternoon after class/work