Built my first Megasquirt
 

Only took a few hours, just got the package yesterday.

Boomslang comes in tomorrow to wire the harness and its ready to be flashed/installed.


https://www.miataturbo.net/~web1_bra...uirt%20002.jpg

https://www.miataturbo.net/~web1_bra...uirt%20003.jpg

https://www.miataturbo.net/~web1_bra...uirt%20004.jpg

So are you gonna go into doing assembly now? I am glad you have the patience to do that stuff.

Is that boost control in the proto area?

-Mike

yeah if someone wants one.

sure is ;)

Looks good, for me when I built mine, I'm really ---- about having everything look perfect (flush to the board, straight, etc) I will say, having a lead bending tool is a great help. Hope the install goes smooth!

On a sidenote, did you test yours with a stimulator?

how are you going to do the wiring in? thats the part I've got to figure out :(

loooks confusingggggg.

nice job tho. +1 kudos for you ;-)

Are you planning on using the VR sensor circuit?

YEAAAAAAAAAAA. It looks so pretty! and confusing.....







(p.s. he is building it for me...:)

if you look closely, it's setup for Hall/optical. Stock ecu will still be controlling idle so i didnt bother with the PWM idle valve mod.

PSSSHHHH you cheated, You copied from your completed one. :bigtu:
Dan have fun with MS it is a blast.

quick, build dan a techedge wb!

I'm working on mine, soon to follow. Should have pics by tomorrow.

What else do you plan on having the stock ecu control? I think i just want to replace the stock ecu with the MS....eventually.

just the fans and idle. its just easier that way, its not mine...it will still be 95% PnP for Rappdan.

So is anyone else using the MegaTunix on a Ubuntu system? Just trying to figure if the Serial to usb doesn't do well on the MS side or the windows side.

I was refering more to the VR adjustment pots, which are only used with a VR trigger input. Thought maybe you had something unconventional planned.

Looks like you are handy with the soldering iron. Nice work.

Is that tape or heat shrink tubing on the red leads?

Karter post pics of yours so we can see what an "---- build" looks like! :bigtu:

its electrical tape...couldnt find my heat shrink stuff...covers up the reisitors soldered on those leads.

You want to make a PnP harness for me and tell me how to do it so I don't have to...:D

dude, scott, are you soldering from the top (component side)??

For me, on the reistors it was easier up top...pretty much a mix of both.

spend $109 at boomslang.us and solder your db37 harness into that. Then you just gotta leave out the wires for the IAT, FP, O2, & EBC.

Or spend X amount on a stock ecu, cut/desolder the connector and wire a male db37 connector to that.

I spent something like 30$ on my pnp harness, but I got the ecu supercheap.

acutally not a bad idea....I've been trying to find a source on the connectors...i know they are very common, but havent tried hard enough yet.

They are fucking terrible is what they are, I have never found an ecu more difficult to pull then the stupid POS miata ecu. The connectors SUCK. I have been having issues with my megasquirt so I have pulled it in and out 10+ times, it doesn't get any easier with time.

Blown stock ecu's are the best price wise for connectors, but they don't come up for sale all that often.

ya. the easier the better for me...just waiting on my 550cc injectors.

mine sits where the passenger puts his feet, takes about 30 secs to access. 90-93 that is.

It is easy to get to. Just the connectors blow.:td:

https://www.miataturbo.net/forums/sh...97&postcount=4

I looked around and it turns out turbo 2nd gen DSM's have identical ECU connections, might be easier to find one of those in a junkyard (it is a DSM!). Other than that check this thread:

http://forum.miata.net/vb/showthread.php?t=235701

Quick question though, Braineack, did you build that MS based on Kags mods to the board, or DIYAutoTune? I haven't totally completed mine yet, was planning on following DIYAutoTune, but I have heard some people have had issues following it.....

onlinecomponents.com

I got sum for my 01 there. whoopie.

I wanted to do the same, but they are out of one of the crimp pin sets I need along with one of the connectors. They have an 8 week lead time.......

He is using kags mods. Him and I have tried both DIY and kags and kags work. We have never gotten DIY's to work with the several MS we have tried on.

Interesting, if anyone from DIYAutotune can chime in here and please help with why your tutorial doesn't work........

If you look closely and read the Spark mod, they describe it different from how it's acutally drawn in the diagram...I trust that if you correct it, it will be fine.

This is the first I've heard of a report that the mod 'doesn't work'-- I know multiple people are using these docs to run their Miata, and the MSPNP is based on this as well with the ignition mods being schematically identical. There are literally dozens of cars running on this exact setup so this is a bit puzzling to hear.

I just looked over our doc to try and find where our text doesn't match the pictures so I could correct it and I'm having trouble locating that, can someone help me out? I want to make it correct if it's got a mistake, and as clear as possible if it's just a bit confusing somewhere...

Jerry, There were a select few on here that had trouble, mine included....I'll PM you about it.

Here's the harness I finished ealier:

https://www.miataturbo.net/~web1_bra...pnpharness.jpg

nice job dude.

Jerry,

I think i figured it out.

Since I didn't build my first MS, I wasnt sure exactly how it was wired, based off your writeup...it was said to have been step by step off your instructions. and I never got spark when it was wired with the resistors off the LEDs.

But I would get spark off r29 and r26. But poking around with a multimeter I figured it out. q8 and q6 are pulled, so that's why. If they were put back and wired like your writeup, it should get spark.

Although I do believe spark 1 and 2 had to be reversed as well.

That's probably it then...

for anyone modding their ECU for use with a Miata ignition system... Kags mods and my mods both work well, but they don't mix well.... you want to pick one or the other and follow that doc exclusively, and also note that the spark output setting and likely the dwell settings are going to be different (for instance, I've heard of people burning coils with more than 2.5ms dwell on 1.8 coils with kags mods, and I'm running something like 5ms dwell on a 95 with my mods to match the stock ECU waveforms as verified with a scope, car is rock solid reliable)

well, that would fully explain why i could never get the diy mod to work.

on another note, aka hijack, can I buy the transistor that is on q6 at radioshack? I'm building an MS2 setup for my upcoming setup and am going to add an additional led circuit to run full sequential COP ign. I just don't wanna have to order a bunch of them and wait if I can pick them up at radioshack and get a few.

Question, why is it advantageous or less complicated to have the factory ecu control something and the MS control something else? Maybe I missed it but what is each ECU's responsability?

Question on your harness. Did you wire the DB37 in parallel as it goes to the ecu or did you cut the wires that the DB37 is routed to? hard to see, thats why I ask.

I have q6 and q8 in.... and I wasn't getting spark with the DIY setup. I switched to the format Neo sent me... which is the same as yours Brains.... and I get spark.

I did happen to start killing my ignitor though... the maps I've used are 4.5 dwell. I lost tach... car runs, just no tach.

The ecu is only now responsible for the Fans and the Idle valve. It's just the way it was done for a while, and it's works. But it's easy enough to give all the control to the MS.

There are a few leads cut that the ECU doesnt see...like the spark output, the rest are still shared.

weird, when i poke around with the multimeter it gets the signal, so it should work, havent tried it yet, but i trust it should.

r29 and r26 bring it to the middle post of q8 and q6, which bring it to resistors that your put to the LEDs.

Pulling the resistors and running it where it is gets the signal before all the reisistors and the transistors basically.

Are you running non-inverted or inverted spark? I was running inverted this whole with the output like you curenntly have. had no trouble for a few months before i decided to go kill my car.

I'm unsure if I am inverted or not. I believe it is Non... its default from the maps I've tried. AL's and Akayreyre's. 4.5 dwell in both for crank/idle and I believe Inverted is OFF.

I wonder if their maps don't get along with the DIY mods... then I went the other board mods and it works.... but it's frying my ignitor.

mines always cold to the touch after driving, so i dunno. I modded mine back to DIYs way to run non-inverted, since I know that's how they reccomend doing it with their mod. always running 5.0ms dwell startup and 4ms running.

Are you running piggyback, or full standalone? And did the tach ever work with the megasquirt?

On the 94, the wire from the coil goes to the tach, but it also goes into the ECU, where something happens (resistor to ground I think). But in any case, with my megasquirt on standalone, the tach did not work until we put (I believe) a 1K resistor across the tach and ground pins in the diagnostic port. Later I fried my coils (at some point the megasquirts settings got fubar'd so my dwell was way wrong). I've since turned to just running 2000 coils (since I had a set), and I drive the tach with the tacho output mod described in the MSnSE page.

-Mike

They're a fairly normal NPN transistor rated at 200 mA, nothing fancy. You can probably find something that fits the bill at Radio Shack.

I had a tach for a bit with MS running. RPM still is working within MS also.

Thanks Mike, I needed this info. Will try later tonight.

I'd suggest building the tacho output circuit. You can get the stuff at radio shack, and it works like a charm. Then you don't have a ghetto resistor in your diagnostic port, and you can run any coils from 94-2000. Tach is pin 2i on the 94 harness, Black with White stripe.

http://megasquirt.sourceforge.net/extra/tachopin.html

-Mike

tach works fine for me, i have been running full standalone for awhile now too. the 1.6 coil directly drives the tach on the dashboard.