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Discussion Starter #1
Here is a summary of this thread

We have measured the injectors for the mzr disi: This thread is littered with videos and pics, and the first 3 pages are definitely a good read if you bored, and a must read if your going to be measuring the injectors yourself.
Some facts:

We can update the pinouts for the MS3 if anyone wants to provide me with that data.
Pinouts on the ecu for a MS6 (you can use the wot box install guides for pinout locations)
Ignition coils:
cyl 1 - 3W
cyl 2 - 3X
cyl 3 - 3Z
cyl 4 - 3AA

Crank sensor - 2C

Cam shaft sensor (i didn't use it) - 2C

ECU injector control line to injector driver
cyl 1 - 3B
cyl 2 & cyl 3 - 3E & 3H (haven't confirmed exactly which is which)
cyl 4 - 3K

Injector wire colors on the injector plug i keep probing in the various pics and vids
cyl 1 - red
cyl 2 - brn/wht
cyl 3 - grn/wht
cyl 4 - blue


The crank:
Confirmed it is a 60-2 wheel. So 60 teeth with 2 missing. (The regular mazda 3 duratec has a different crank).
See the picture below. The engine rotates clockwise. So that means the missing tooth/gap is 120 degrees BEFORE TDC on cylinder 1 compression.


Firing order is 1 3 4 2.

The 4 injectors are controlled by both a + & - control rails. The - controls are specific to each cylinder. The + controls are shared between cylinders 1-4, and 2-3.


The injectors are likely controlled with logic like this:


If you monitor one of the injector lines (not ecu control line, but direct line to injector) you will see both the actual opening event, and also the + switching between 1-4 & 2-3 connection. The injector is not spraying twice though.


Spark:
QUOTE
The spark actually happens at the end of the pink trace (falling edge). When the signal is high, it is charging the coil. When the edge falls, the spark happens. I counted about 18 crank pulses from the missing tooth to the end of the spark event in this picture. Every crank pulse is 6 degrees. So 6*18 = 108 degrees. Since spark happens at 10 degrees before TDC, that means it is 108+10 = around 118 degrees from the missing tooth to TDC. Which is correct. Nice capture!
[/b]
During shifts, the injector may sometimes spray after the spark event.


HERE'S THE JUICE OF THE THREAD
When fairly bolted, and near redline, the injection cycle will extend all the way through the intake stroke and into the compression stroke, and depending on the fueling requirements, it'll get damn close to the spark event. This has some serious implications:
- Fuel injected from the injector depends not only on the fuel rail pressure, but the differential pressure between the fuel rail and the combustion chamber. As you start spraying further and further into the compression stroke, the injector requires more and more time to spray a given amount of fuel. You can almost think of this as a redline for our injectors, higher rpm's may not result in higher power beyond a certain point.
- For proper fuel atomization, time & fresh oxygen is required. We have a swirl type injector injecting at around 12MPa in a wall guided system. This is pretty much AS BASIC as it gets with direct injection.QUOTE
I have an SAE paper in front of me quoting 3ms for complete vaporization. At 6000RPM 3ms = around 110 crank degrees. If we are still spraying let's say even 40 degrees BTDC, that means unvaporized fuel will exist well past 70 degrees after TDC and by that point it's too late to get power out of it. We get soot.[/b]
- Mazda's Direct injection is limited to a maximum of 50% duty cycle, consisting of the intake stroke and compression stroke.


Potential fixes for a maxxed out DI fuel system:
1) Bigger injectors
2) Secondary fueling
3) Increasing fuel pressure



To see all of the vids and pics and stuff, you'll have to visit the link below or pm me with specific requests, cause i can't copy the entire thread, ha. We learned alot of shit. Above does a good job paraphrasing the discoveries. Any will keep this summary section updated if/when any pertinent information is added to either thread. I'm glad we finally got to do this. Hope it helps.

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I'm tired of double posting, so here is the thread.

Aviator, i know you can't post over there, so i'm gonna ask hal if he'll re-instate you or some shit. Regardless, once everything is finalized and all the details smoothed out, i'll post all the facts here, cause i think it's definitely important to those of us after power.
 

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Discussion Starter #3
Yup, some videos are up.

First blush, my injectors are pretty much on from TDC on the intake stroke all the way til the spark plug fires, and occasionally it will keep injecting fuel after the spark event on a shift.


possible implications:
- not positive, but it doesn't look like there much more room for me to inject more fuel. I'm running a 3071 on stock exh manifold at like 20 psi @ 5500ft and not sure how much further i can go. If the injectors open any earlier, it'll be spraying during the exhaust stroke. Any later and it'll be spraying during the power stroke. Hmmmm.
- even less positive, but seeing the injectors spray after teh spark events during shifts makes me wonder if it could possibly damage teh injector. Hmm, injector damage during a shift, go figure.


Once the big brains over there digest some of the info, i'll update this thread with all the pertinent infoz and conclusionz.

Here was my first post over there, and some discovery ensued:






Okay. So today i attempted to measure when the injectors open. I still have no clue when they open.

Time for lex and 06speed6 to chime in. I'll leave all my wires in place so i can continue measuring any additional shit anyone wants, just need some help gaining my bearings.

From the beginning:

I wanted to measure 3 different events, Crank Shaft sensor, ECU injector ctrl line for cylinder #1, and ECU spark ctrl line for spark #1.

For the crank sensor line, i used the exact same one as used in the wot box, here's their install pic:


For the spark line, cylinder 1, i used pin 3W from this install pic for the wot box:


The injector circuitry was a bit more difficult, and i got a schematic from Jon at N2MB performance (Jon rocks the shit, good guy).


You can see the injector driver module in lower left hand corner. I assumed, that the indicated lines were control signals from teh ecu, because they map all the way back to it.




I made up some handy probe tools to stab the wires, saving me the trouble of splicing and stripping (but i do like to strip ;) ).



I had no clue what ctrl line controlled what injector, so set up my scope and mapped them by monitoring both the actual drive circuitry with the ecu control logic. *edit* I had incorrectly mapped the ecu control signals. I had chosen cylinder 4 for 1, read below posts for clarification.
All these pictures look the same, but basically it was me matching injector driver line to ecu control line.





So thought the universe was great, and lady fate was on our side. I called my buddy adam (koukis14) to come over and video the scope for me. I didn't really take a hard look at any of the traces on the scope yet, just knew that everything was hooked up and working right, car started, scope powered with the inverter etc.

Once he got here, we started studying the traces. Shit didn't seem to "add up".

important stuff
Here's a pic of the scope trace we were staring at:


Ch 1 is the crank (yellow), and as i suspected, it has data for many many sub-degrees.
You can see the "gap" section in, which maybe corresponds to the missing tooth lex mentioned.

Ch 2 (blue) is the ecu's ctrl line for the injector on cylinder 1 (assuming the pdf i got from jon is accurate, which i'm not 100% sure since it's from a source other than mazda).

Ch 3 (pretty pink) is the ecu's ctrl line for spark for cylinder 1, base on above wot box schem.



The pic shows something that is not possible (or at most, completely illogical), here's why
-Why would spark happen before the injector?
-Why would spark happen after TDC, assuming the gap in the crank signal = TDC? That means it'd either be advanced by like 360 degrees or retarded.


So we decide to start probing the actual injector driver along with the rest of the stuff we had from the ecu, and we realized a few things.
- The actual voltage signal on the injector lines (the ones i used to correlate to ecu control logic) was happening twice as often as we thought, but it was outside the span of the scope window. So basically there was the spike like in the pics above, TWICE as often as the control signal from the ecu. I'm not sure if this has to do with the inductive load, or some circuitry in the injector driver module, but it was definitely happening twice the rate of the ecu logic.

- We also noticed that the cylinders 2, 3 & 1, 4 seemed to have injection events at nearly the same time. But maybe since the scope was picking up double the real injection event, 2 & 3 are actually 360 degrees out of phase (crank degrees), and 1 & 4 also 360 degrees out of phase (crank again), and the two groups out of phase by 90 or so. I'm not sure.

I can think of two ways the motor would run (i'm probably showing alot of noobness here), one where cylinders 1 & 4 and 2 & 3 fire together, out of phase from each other but firing in groups of 2.

or one where each cylinder fires 180 degrees (crank degrees) out of phase from all other cylinders, with only one firing at a time. If this is the case, then maybe i correlated the wrong injector to the wrong ecu event, and there should have been a correct ecu control event that makes everything else make sense.

Here's a video of the mayhem, taking forever to upload: In the vid you can see how there are 2 injector events for every 1 pulse from the ecu ctrl line, and how things would work beautifully with 2 assumptions:
1) the gap on the crank signal represents BDC instead of TDC. I have no clue on this
2) I had incorrectly mapped the wrong ecu ctrl line to real life injector pulse because there are 2 pulses for each ecu event, so you can assume the odd pulse is the legit one. Also if you go back and look at the 4 pics where i tried to match ecu logic with injection pulse, there are overlaps of the curves, with one jagged looking blue curve and both a flat and notched yellow curve. This was the double pulse event, but i didn't recognize it.
SANY0038.flv video by djuosnteisn - Photobucket


If anybody has actually read this far, then i know they care, lol, and i'll do whatever i can to fucking measure this right, but i need some directions from the seasoned folks here.
Take your time, digest what i posted, and ask any questions you want. I'm going to leave all the shit hooked up till we get the right measurements, and then i'm gonna go rip around like samsel with a scope on my forehead, lol.



Right now i'm going to go out and solder what i think is ecu control line #4, cause if i mapped them wrong originally, this would be the correct one. If it works, and shit looks dandy, i'll let everyone now and clean up this fail ridden OP.




Here's me realizing there were two injector events per injection, thus making me think ecu logic for injector #4 was #1. Now it's all sorted out:
Originally posted by Lex;333418
NICE! The crank signal is correct. The spark signal is correct as well.

The gap in the crank signal is the missing tooth. I think there are 32 crank teeth in total with 2 missing. Crank your time scale a little bit and you will the many missing teeth.

Spark is correct because the event is happening close to TDC (the missing tooth on the crank at idle) It's around 10 degrees BTDC. The missing tooth might not be exactly at TDC although that is a little strange

The crank spins twice (720 degrees) per engine cycle. So the missing tooth in the crank signal you will see twice for every injector and spark event. The missing tooth you will see every 360 degrees.

So are you unsure if that's the right injector you probed?

From what I can see, it's happening on the exhaust stroke (after the power stroke). So something is up.

Very good stuff so far!!!

After u get inj 1 figured out, are you going to be able to drive the car under load?

Also, you can probe the spark right at the coil pack. The igniter has 1 power, 1 ground, 1 signal line.
I got the injector shit figured out.

Not sure why there is two pulses on the injector line from the driver to the injector, but there is. It's probably due to some sort of inductive fly back on the coils or some shit. Like a voltage when the current starts, and a voltage when the current stops, but why they're both positive is beyond me.

Regardless, i had cylinder #4 for cylinder #1. Here's a pic with the real #1 control line and the real injector pulse. Looks real good.



Yellow is crank, pink is spark, green is the injector control line from the ecu, and blue is the actual voltage on the injector line.


Only other discrepancy is the crank "missing tooth". I'm now 99% sure the missing tooth, or at least teh gap in my crank scope trace corresponds to BDC, not TDC. If you pretend like TDC is in between the crank pulse, then halaluya, things work out.

Some facts:
Pinouts on the ecu for a MS6 (you can use the wot box install guides for pinout locations)
Ignition coils:
cyl 1 - 3W
cyl 2 - 3X
cyl 3 - 3Z
cyl 4 - 3AA

Crank sensor - 2C

Cam shaft sensor (i didn't use it) - 2C

ECU injector control line:
cyl 1 - 3B
cyl 2 & cyl 3 - 3E & 3H (haven't confirmed exactly which is which)
cyl 4 - 3K


Injector wire colors on the injector plug i keep probing in the various pics and vids:
cyl 1 - red
cyl 2 - brn/wht
cyl 3 - grn/wht
cyl 4 - blue

.




Here's lex figuring out where TDC correlates to the missing tooth on the crank:

Originally posted by Lex;333767
The spark actually happens at the end of the pink trace (falling edge). When the signal is high, it is charging the coil. When the edge falls, the spark happens. I counted about 18 crank pulses from the missing tooth to the end of the spark event in this picture. Every crank pulse is 6 degrees. So 6*18 = 108 degrees. Since spark happens at 10 degrees before TDC, that means it is 108+10 = around 118 degrees from the missing tooth to TDC. Which is correct. Nice capture!



As for logging the injectors, nice video! That shows me the command from the ECU is enough to look at.

I can't tell from the video if the ECU moves WHEN it injects around. As you see, when you rev it, the crank pulses become faster. So this might be tricky, but keeping the missing tooth on the screen will give us the reference needed (as long as we can still count teeth). Are you logging on the scope itself or taking a video of it? If taking a video, vary load very slowly with a passenger and change the timescale as RPM and load increases so that you can still see the missing tooth.

Great stuff so far! We're getting somewhere!


.



And here are some goodies! Everyone likes vids and pics!

So here are some vids, triggering off the rising edge of the fuel injection event (when injection has stopped). The scope was set this way from when i used it last, and i didn't think to change to falling edge for beginning of injection event until later (cause i wasn't the one looking at the scope, i was the one with tight sphinctor going 140 trying not to kill us, lol).

Here's a 3rd-4th vid with a datalog to match
3-4datalog1.flv video by djuosnteisn - Photobucket

Boost curve on teh 3rd gear portion looks a lil fucked up, but that's cause i rolled into it wierd, the rest of it is legit and a good representative of the boost & afr's and slight creep i experienced.

Here is a 2-3-4th, it looks pretty good and filmed well:
2-3-4good.flv video by djuosnteisn - Photobucket

Here is a 2-3-barely 4th. You can see how the injector spray will overlap with the spark event slightly. I think this happens at teh shift point.
2ndto3rdtolil4thgoodoverlap.flv video by djuosnteisn - Photobucket

Here's 2 vids of 2-3-4 i think after i started triggering on the falling edge (injector beginning). It helps kinda with seeing the injector event relative to crank signal. There is glare, but you can see the cursor in the upper right hand corner, this is when the injector opens.
starttrigger.flv video by djuosnteisn - Photobucket
starttrigger2.flv video by djuosnteisn - Photobucket

Some things to note:
- The injection event is taking up ALOT (read ALOT) of the intake stroke. And you can see how close it gets to the spark event (which when at wot is usually no more than 12-13 degrees BTDC)
- The injector appears to start spraying quite near TDC on the intake stroke. Adam and i did a pull, and stopped the scope at 4500rpms, and counted 24 pulses (to the left of when the injector starts) between the pulse (missing tooth) of the crank sensor. We did the same thing again and stopped the scope at like 6300rpm, and only counted 21 pulses..... so to summerize
...4500 rpm: 24 pulses between missing tooth and injector opening
...6300 rpm: 21 pulses between missing tooth and injector opening

That's about 18 degrees or so moved to the left in the higher rpms. So for the most part, the fuel injector will just stay open longer (closer towards the spark event, as evidenced in the videos), but maybe if it has to, it will move to the left (closer to TDC of intake stroke) a bit, not much, just a bit.

- The time scale during all these videos does NOT change, so as the crank signal and spark event start to squeeze in (cause rpms are increasing) the amount of fuel injected is going to be pretty much constant. We are looking at a single cylinder event, so the amount of fuel injected is pretty much constant across the rpm range (boost creep probably offsets some of my ve lol, keeping my torque decent ish, not sure). My afr's stay right in mid 11's throughout wot.


Have at it guys. To me... This looks like at my power levels (3071, dynoed at 355 sae corrected, so not as powerful as many people at sea level, but definitely not weak) i'm already looking at a very little room for further fueling. But maybe i'm missing some stuff here.

I'll still leave everything hooked up for another week and i'll drive my jeep, but i have to bring the scope back to work during the day lol. I think the vids give us exactly what we need, so not sure what else anyone would want me to film, but just cause it's alot of setup time, i'll leave it hooked up.
 

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Discussion Starter #5
Hitatchi AFAIK, but there isn't much info on them. I really don't know much about them at all.
 

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good info. Does seem weird that the injector is spraing after spark during a shift. Wonder if that has caused a detonation during downstroke due to a second "combustion" event or something. Or if due to the extra fuel the combustion event was still taking placed after BDC and bang rod/piston/pin fails...doubtful, but a thought.
 

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QUOTE (aviator79 @ Oct 12 2009, 04:56 AM) index.php?act=findpost&pid=1608124
good info. Does seem weird that the injector is spraing after spark during a shift. Wonder if that has caused a detonation during downstroke due to a second "combustion" event or something. Or if due to the extra fuel the combustion event was still taking placed after BDC and bang rod/piston/pin fails...doubtful, but a thought.[/b]
Even if combustion was still occurring after BDC and into the exh stroke (this does happen quite a bit) it would more so heat the fuck out of the exh valve and turbo and stuff. Some drag racers will intentionally run way too rich and actually retard the timing to intentionally push an igniting exh combustion into teh turbos and get them to spool quicker. I'm not sure if it could contribute to our motor failures, but anythings possible!
 

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What's wrong for spraying during the power stroke. This may sound stupid since I am not familiar with cylinder pressures, but if your spraying at 1800 psi and the cylinder pressure has not reached 1800 psi., there should be some time for overlap. Are you taking this into account already. Is there a way to spray a little extra fuel in?
 

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Discussion Starter #10
It probably woudn't hurt anything, but i don't think it's going to contribute to building that much more power. It all depends on if there is any more un-burnt oxygen around the injector after ignition, and if and where the flame front is relative to it. Honestly, i'm not sure at all, lol.
 

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Well I forgot the exhaust valves would be open after BDC cause im a tard and I didnt relize other s did this, but some problems that could arrize are that there is no no time for air and fuel to mix and fuel to atomize and also you are in a sense cooling the combustion event but that likely doesnt matter much, but this is certainly why I get backfires during shifts. So if we could control duty cycle what would happen if you stoped this from hapening. Why does it happen? I have to reread your post as I only skimed throu it, but great stuff. Added to the FAQ, and keep it up. Great pokers for getting readings off the wires. Less damaging then sticking the pointed lead thru the insulation.
 

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I guess i should be happy that my poker isn't damaging. We can just say my poker is perfectly sized ;) .

Other thread is getting pretty good. I'll update this one tonight with some of the infoz. I'm still waiting on some input from corpus and lex.
 

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Ya, I read it over there, but keep us posted over here if for no better reason for the FAQ, and me that dont get to post over there.
 
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