Software malfunction?? ||Solved||

[AlanJ]

I have been banging my head for a couple of weeks now with no success.

here are the quick details Quick details,

ms3 built and tested, v3.0 board
ms3x expansion added,
tuner studio ver 3.0.18
firmware 1.5.0 released 20170116
engine,
1992 dodge Dakota 3.9l V6 with all stock sensors, 6 injectors, one coil, with distributor.
added 36-1 crank sensor from diyautotune with the pickup sold by them as well.
ms3 controls - overdrive, ac, fan, torque converter lockup, and alternator.
6 injectors connected to the ms3x card, spark using js0 spark with the board mods.

no matter what i do i can not get the ms to fire the number 3 and 5 fuel injectors.
in the test mode i can fire the injectors. the engine runs very pour, and jerks. rock solid timing no drift up to redline. no sync loss issues.
when i physically disconnect number 3 or 5 injectors there is no change in engine operation. when i use the software
to disable 3 and/or 5 there is no change. all other injectors cause the engine to almost die. spraying starting fluid into the intake while running
fixes the rough idle and pour running until i stop spraying. narrow-band fluctuates like a cyl is missing.

i use a pwm output to control an analog tach, above 2500 rpm or so the tach is erratic, shuts off, pegs out and does other weird things.

The weird part.

when i use the injector test mode to fire the injectors they work as expected, all 6 individually.....

I need pointers where to go from here, these 2 injectors do not fire under any modes, batch sequential or semi. but work when using the test mode of tuner studio.....
i have tried many different settings. its almost as if the ms is at its limit of processing power and giving up on these 2 injectors, even though i know this is not the case.

i have reloaded the firmware, roled back to older firmware, installed new firmware again and used a second computer to start a totally new project.

i have access to an oscilloscope and am good with electronics. please point me in the right direction...

don't laugh if the issue is obivous..... unless its really really obivous.....

logfile to large to upload (20mb) looking how to shrink it <----- Edited and added

[whittlebeast]

You are having issues with your main power supply. If you look at SecL it is a counter that counts up to some fixed number and the start over at 0. Yours is resetting at all sorts of places.

Andy

[AlanJ]

Checked out the power supply. The voltage is good, the ground to the mega-squirt is suspect, I am currently replacing it...
New log file coming soon... Inside the mega-squirt I do not see any power spikes or dips on the oscilloscope.
The outputs to the injectors still are not functioning. Second Guesses?

[whittlebeast]

I would verify that with a fire order of 1,6,5,4,3,2 that channel A spark is going to cylinder 1, channel B spark is going to cylinder 6, channel C to cylinder 5...

My bet is you will find two channels are swapped.

Andy

[AlanJ]

The ground issue fixed the ms from resetting, new logs attached. these are directly from the ms. its much easier to log from there now that its working, considering i'm basically driving with an electronics lab in my truck.

I am using a single coil with distributor, I will check the firing order again. Ill be looking at those two plug wires and swap them just to see... I just replaced the plugs, wires, and cap because of the issue. I pulled them all off and ran them in an alternate location, I will verify tonight. The odd cylinders (1,3,5) were White and pitted. the even ones (2,4,6) were black and sooty.

The Tach output was fixed last night. The curve settings were incorrect. My mistake.

Edit:

Checked plugs, they are in the correct order. swapping them makes the engine backfire through the intake and engine die. Oscilloscope shows no signals to those injectors after cranking. The priming and, cranking pulses are okay, as soon as the engine passes 400 rpm the 3 and 5 injectors are not sent another signal until the engine stalls or the key is cycled. Could this be an interference issue? how can i tell by the logs when these should fire or what phase the engine is on? looking at the composite logger I'm trying to figure out where each cylinder should fire, and making another input to log when they actually do fire.... i can not tell what phase the mega-squirt thinks the engine is on, i can only look at the logger and cam triggers to figure out where it actually is.......

[jsmcortina]

Please post a regular datalog. That will include all datafields.

James

[AlanJ]

Issue resolved, the first generation Dakotas are known for their bad factory wire splices. Apparently google forgot to tell me..... The splice for the odd injectors was corroded and not functional. The voltage while running was fluctuating and would not hold a load. I don't understand why injector number one was functioning but that is for another science class. I soldered the connection and added shrink wrap, as opposed to the smashed wires, and fiber tape the factory thought would last....

The engine is running great now. Thank you all for your support.

One last question on the operation of the mega-squirt, In sequential mode, and selected "end of squirt", Is the intake cycle determined by the start of the down stroke or the middle of the down stroke?

Admin -- Please change title of thread to solved.