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Weird fuel pwm on MS3/MSX

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Hi, I have an issue and is a weird behavior on the fuel injectors, it's seen from datalog, so I assume that it is a misconfiguration :(, but I don't find the problem. Behavior, on cranking it pwm is at 24ms, or more, then lows down to 1ms, and then up and so on, it revs on 24ms then stop. But its on datalog, so problem is with tunerstudio and ms3 itself. It's on first start stage tho, any clue of what configuration can be messing?, after start enrichment is a bit high now because of testing, but is weird because it should slow down to half pwm, not to shutdown

Thanks in advance





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I would guess that your run/cranking threshold is a bit too high. When the engine speed is below that threshold, it used the cranking pulse width (which must be huge), and when above that it uses the main fuel table (1.6 ms).

ok, so I just made a test, and notice something, main table is running too little fuel, I lowered the cranking percentage to make about 15ms, and rise threshold up to 700rpm, and almost make it stable, so I don't know why I'm running in too low fuel at 100ve, 1.6ms is not enough, I send to clean the injectors, fuel pump is new, and the original dme was working good, verified injector size by item number, is rated at 19lb/hr or 199.5cc/min, wiring is ok, all injectors are working and in correct sequence here is my datalog

P.D: I'm going to check the fuel pressure regulator, I'm between fundamentals and practical tuning, and doing math, It should Idle at 1.5ms, thanks for help tho



Ok, issue fixed in my case, well, it results that the tank ventilation valve wasn't opening by the stock dme, so connected the signal wire to a relay and ignition and is working now, it's one of those issues out of the book, thanks for the help