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MicroSquirt v3 no inj bank alternate firing
Posted: Wed Aug 23, 2017 8:32 pm
by GrocMax
Either 3.83 or the latest MSExtra cannot get uS v3 to fire inj1 and inj2 alternately. ALWAYS fires simultaneous. Played with it on the scope/AWG for hours. Tried about every combo of crank/cam triggering possible with the wave generator.
What am I missing?
Re: MicroSquirt v3 no inj bank alternate firing
Posted: Thu Aug 24, 2017 11:43 am
by GrocMax
Has anybody ever actually scoped one?
Switching from simultaneous firing to alternate firing with NO OTHER CHANGES does nothing but double the PW. Both injector channels still fire simultaneously.
What's going on? What am I missing here?
Re: MicroSquirt v3 no inj bank alternate firing
Posted: Fri Aug 25, 2017 6:18 am
by Matt Cramer
Can you post your MSQ and the scope traces from testing?
If you try running just one bank in output test mode, do both fire or just one?
Re: MicroSquirt v3 no inj bank alternate firing
Posted: Fri Aug 25, 2017 6:46 am
by GrocMax
I'll revisit this in a bit, I found another manual at the MSExtra site that has conflicting information on what inputs to use for crank/cam sensors and how they are to be wired, totally different than the instructions at useasydocs (!!!?!?!??!!!!!!!). I was under the impression that the crank signal input type had no bearing on whether it was able to alternately fire the injector channels, but even with a missing tooth wheel with a sync it won't. Was using opto to receive a square wave form generated remotely. It doesn't like 36-2 or 60-2 square waves.
2.92, 3.83, and the MSExtra behaved the same.
Trying injector output test just killed communications and it locked into test mode.
Re: MicroSquirt v3 no inj bank alternate firing
Posted: Tue Aug 29, 2017 6:40 am
by Matt Cramer
Have you confirmed the RPM reading is above cranking RPM?
Re: MicroSquirt v3 no inj bank alternate firing
Posted: Tue Aug 29, 2017 11:52 am
by GrocMax
Matt Cramer wrote:Have you confirmed the RPM reading is above cranking RPM?
Scope is putting in a 12-1 square wave at 50Hz (or whatever I select), and ECU shows the correct RPM of 3000 RPM. 50 * 60 = 3000. There are no crank sensor input anomalies, its steady.
Yellow- crank signal from AWG into VR+ at 50Hz
Aqua- ign1 output set for 0 deg firing seems to be correct on rising edge of #1 tooth 2mS dwell.
Green - #1 inj
Magenta- #2 inj
inj 1-2 have 0.5v offset for clarity and set to fire 0 deg, 2mS pulse with approx. .690 dead time.
Sensors are simulated with rotary pots, coolant temp around 180F, intake temp around 120F, TPS 50%, MAP 100kpa.
Ignore the noisy look of the traces, haven't used this scope setup enough to figure out optimal filtering or trace setups, and I wouldn't claim its a lab quality unit. Its probably a grounding issue as the AWG crank sensor simulator trace is clean, only the ECU outputs look fuzzy.
