New install

[binlki1]

Hello all
Here's what I know. I have a 91 Nissan 240sx stock. I'm installing a MS3 v3.0 with a mx3 expansion board and a mapdaddy 4 map sensor (NEW INSTALL). Wired and setup for full sequential spark&fuel, Coil on plug using Denso 4 wire logic coils, stock injectors(hi Z) both coils and injectors wired to mx3. Harness I made up . Installed 12 -1 trigger wheel that I purchased from Diyautotune. Unplugged the orginal loom, overlay-ed my new loom and plugged everything up. Calibrated sensors TPS, ClT and IAT. Engine turns no start or seem to fire at all. Checked timing with light, timing marks not visible. Confirmed orientation of trigger disk. It checked out. Reclocked the distributor till I could see timing marks on balancer. It finaly fired and almost started ( it reached about 500rpm +or- ). cranking pulse width around low 30s if I change the cranking pulse width and bring it up in the 50s it tries to start. It sounds like its firing late so I start checking timing. Back to basics pull #1 plug bring motor up to TDC compression stroke timing is 180 out. Pull distributor reclocked it back to default and try to start nothing wont even think about firing. Ok I emailed DIY to ask them about my setting and installation of the trigger disk. Mean while I unhooked my loom and reinstalled the original loom set distributor back to where it is suppose to be uninstalled the 12-1 trigger, installed the original trigger . Still wont start, cleaned plugs adjusted distributor timing slightly and it fired off. Ok now Im now back to where I started motor runs. Now I reinstalled 12-1 trigger, loom, and my MS3. same result as before nothing. I started playing with the setting in tuner studio, and found if i change the tooth 1# angle BTDC from 345 to 400 I at least get backfrire in the exhaust. Ok I may very well have other problems but if you have spark and fuel and no start doesn't that just leave Ignition timing at least for initial startup. Oh I almost forgot I have tested with the stim and everything seams to work properly on the bench.

Any help or opinions or direction would be greatly appreciated.
Thanks
Kirk Bingham

[Matt Cramer]

Please also attach a data log of an attempted start.

[binlki1]

Hi Matt
Here is the datalog

Thanks
Kirk

[billr]

I would change it to "wasted-COP" and get the spark timing correct like that, do that with plugs out and fuel disabled, no use wasting fuel and stressing the starter until spark timing is verified.

[binlki1]

Thanks Bill I will give that a try. Should I change the tooth 1# angle BTDC from 400 back to 345

[binlki1]

hello all
I just thought I would let everyone know it starts . I also had a message in to diyautotune And this was Phil Koch's direction " This sounds as if you have not yet set or adjusted your base timing or trigger angle offset. Simply set the ECU to fixed timing at 10 or 20degrees and use a timing light to check. Begin changing your trigger angle offset until your crank shows 10 or 20 degrees timing on the trigger wheel as you have set the ECU to match. Currently your ECU and physical trigger wheel are not aligned.

Of course he was right however the directions for the 12 -1 trigger wheel say to use 345 deg #1tooth angle offset. I ended up with a setting of 20 deg.

So here is where im at now. It starts and runs a little then dies. Pulsewidth jumps back an forth from 32 to 6 depending on rpm. the other thing is that i had to change from speed density to MAF which wasn't part of the plan just yet as I was under the impression you had to calibrate for your particular engine. This one is off a 90s v6 mustang.( Let me guess the map also needs to be calibrated to). I was only going to use the IAT sensor for now and bring the rest up later.

Thanks bill

I would change it to "wasted-COP" and get the spark timing correct like that, do that with plugs out and fuel disabled, no use wasting fuel and stressing the starter until spark timing is verified.

this came in very handy and it makes the strobe work much better.

It seems to me to be a fueling issue since you can't give it any throttle and the MAF needs to be calibrated. Any advice or direction is greatly appreciated.
Thanks Kirk

[billr]

Why did you have to switch to MAF-based control, would it not start at all with MAP (do you mean "speed-density"?)? The WUE looks kind of low, so you could try bumping those numbers up to get it to run longer than a few seconds. Also, changing to 2-squirts and alternating would minimize injector dead-time effects, if dead-time hasn't been measure accurately and with your drivers.

As always, post current tune and run logs. Changing from SD to MAF is a fairly important change, so a new .msq is especially needed!

[binlki1]

Hi bill
Yes I changed from SD to MAF, best i recall it would only fire and wouldn't catch. I will try the changes you Suggested. And post new msq and datalog. I will swap back to SD and test as well post msq and datalog.
Sorry about not posting logs I have a desktop. I keep moving back and fourth for internet connection. My tablet is wireless will try logs with it.

Thanks
Kirk

[binlki1]

Ok here are MSQ'S and datalogs for both setups SD and MAF.
Hey Bill I changed WUE and sure enough it does idle longer. Still wont run setup SD though.

[binlki1]

maf msq file

[billr]

A few more things to consider, primarily in relation to SD:

Set "cranking speed" to just above actual cranking speed, probably about 250 rpm; that way all the table parameters come into play as soon as it actually fires. (Probably not a problem here, though)

Set "cranking (spark) advance" much lower than 25 deg, I like to use zero. The way it is right now, as soon as it fires and gets above the present 500 rpm "cranking" threshold ignition timing retards (from 25) and tends to kill the engine.

Increase the WUE some more, at least for now, the WUE fueling is still quite a bit leaner than the cranking. A fairly rich engine will usually run, crappy maybe, but run... a lean one tends to die. Set the last bin (highest temperature) for 100% fueling, then WUE will be out of the equation once the engine is warmed up.

Still no firing on SD? I'll have to study those logs some more...

[billr]

MAP seems to drop pretty quickly when the engine fires, the throttle idle opening (whether hard-stop or IAC) may not be enough. Try using the throttle a bit while cranking, just don't exceed the 70% that invokes "flood clear" and stops injector pulses.

[binlki1]

Thanks Bill . I will make those changes now. Any idea why SD doesn't work as well MAF. It does run a little under SD but not as well as MAF. Duh I should read more closely

[binlki1]

Bill I made the changes. SD runs a little better/longer. MAF still runs better/longer, if cranking rpm is lower than 500 it won't continue. Pulse width is still back and fourth from 32 - 8. 02 is all over the place. I have a registered version of TS should I let it autotune? It smells very rich but it won't take any throttle.

[billr]

Want to try an odd experiment? Raise the "cranking speed" to about 3000! That way it will be running on the "cranking pulse" only, let's see if it will run for more than a couple of seconds that way. Also, if you have set "cranking advance down to 0, as I suggested, then raise that back up to about 10, as that will be what it will have while "running" in the cranking rpm range.

[binlki1]

OK will do. its kinda running it bounces back and fourth cranking /running. Try now.

[binlki1]

Bill
Setting cranking rpm to 3000 didn't seem to change anything. When it catches it jumps up a little by not that much 1200 at most . new datalog and msq shortly.
Thank you very much for your help.
Kirk

[binlki1]

latested msq and datalog

[billr]

I have little understanding of MAF-based fueling, you better wait for somebody else to join in here...

[binlki1]

Im not opposed to switching to SD getting that working then bringing up th MAF later. Im still puzzled that SD won't work properly do you think I have a phycal problem or it software? Any thoughts on TunerStudio and auto tune. It doesnt seem to be helping anything.

Thanks again for your time and help