Megasquirting my stock '99 NB
 

Hi guys,

I'm planning to install a turbo, probably a BEGI-S, in my '99 10AE. Before I do that, I need to rebuild the bottom end (leaks around the rings).

Before I do any of that, I'd like to get the Megasquirt installed and get some experience tuning it. I'll be doing a parallel install, to allow the stock ECU to control the alternator, AC, and basic OBD-II stuff for emissions testing. I may go full standalone sometime in the future, but I want to start here and learn how to tune the device.

I've been following Braineac's Post, but I'd like to get my Megasquirt pre-built so I don't have to learn assemble boards. I'll save that for another project, if possible.

Is thispre-assembled MS-1 pcb2.2 the right starting point?

To build my boomslang-style harness, I need a Megasquirt Tuning Cable (DB9 straight-through), a 18" Megasquirt pigtail harness, and a bunch of 64, 26, and 22 pin connectors. Does anyone sell the wiring harness pre-assembled for a parallel install in the NB?

I've also seen mod-kits described, but I'm not sure which ones are necessary for an NB parallel install. Do I (or will I, once I build the turbo) want the IAT, boost control, or relay fan control mods? I understand I don't need the IAC if I am running in parallel.

Are you planning to put the '97 or earlier CAS in place? Right now the only ways to get MS1/Extra to run on an NB are to install the earlier CAS or a missing tooth crank trigger.

I strongly council against purchasing the R2.2 pca. The R3.0 board is a much nicer design, and the cost difference is trivial.

If you were to use the MS-II CPU as opposed to the MS-I, you could use the stock NB cam and crank sensors and not have to deal with an NA CAS.

One option for your harness would be to purchase a "factory harness extension" from Boomslang. This product is exactly what the name implies- just a plain ole' male-to-female extension that goes between the factory ECU and the factory wiring. The idea is that it gives you a convenient place to do all your cutting and splicing, making the MS essentially a plug-n-play device. So on this extension, you'd cut the injector and ignition lines and bring the car-side of them over to the MS, tap into power, ground and the sensors, etc. The pigtail harness could be used for this purpose, though honestly it's not that hard to solder some wires into a DB37.

you can buy the same thing from DIYautotune prebuilt. they can even do the mods for you. then its a matter of buying/building a harness.

Yes, that's the plan if I go with the MS1 I mentioned above.

I didn't realize this was possible - all the posts I've read here and on m.net talk about using the MS-I and NA CAS.

I'm not too worried about the trivial cost differences - I just don't want to be too close to the cutting edge. I travel all the time for work, so my quality time with the car is limited to Saturday & Sunday. I only want to spend part of that time under the hood (or upside down with my head under the dash) ;)

How many folks have had success with a parallel install on an NB using the R3.0 board?

Is that in addition to the preassembled kit I mentioned above? Or would I be asking them for a "special order" with mods already done?

Do I need the same mods for an R2.2 or an R3.0 board? MS-I CPU vs MS-II CPU?

you want the v3.0 board assembled kit. MS-I, with miata mods.

You can email us at websales@diyautotune.com to set up orders for special order ECUs.

The only MS2 on NB stock sensors I've seen personally is AbeFMs, but then I've only seen two NB installs in total, and one of them we just did yesterday. Abe originally ran parallel, but finally manned up and went full standalone.

Incidentally, you NB guys have the most frakked up ECU location I have ever seen. :D My back is killing me today.


Seems like a strong argument in favor of using an MS-2, not having to install additional sensors, and building an inline PNP harness. On Saturday morning you can stick the new harness in place between the ECU and the car, play with it, and come Sunday afternoon if you're not happy you can pull the harness out and be back to stock for the week.

And of course, using an extension harness means that you can do all the wiring sitting comfortably at your workbench, rather than standing on your head under the dash.

Probably more than have with the R2.2, given that very few people are buying the 2.2 anymore. That board is essentially obsolete, and I have utterly no idea why they are still being sold as new. Functionally, the two are quite similar (and in terms of their I/O pinning and such they're identical except for the additional I/O on 3.0 which 2.2 doesn't have), mostly the 3.0 just has more space to work in, fewer hacks required for operation, better power and ground distribution, etc.

you know, ive been trying to follow along with abe's read up because im planning to switch over to MSII for stock sensors. The NA CAS apparently is a POS, and i get misfires and OBD check lights like no tomorrow.

where would i find the correct schematics for the stock sensors? thanks guys.

Don't Worry. Your Posture will straighten out with that nice ergonomic Nardi Torino :D
Thanks so much, again. That was totally AWESOME of you guys to help me as much as you did and I dont think I could ever thank you enough to repay what an invaluable service you guys performed for me. and BTW I ordered the LC-1 With a red Gauge. I just figured, 'do as the romans do' I'll also be ordering a tablet and fabbing up a mount similar to yours.

Maharashii, Listen to this guy. Him and AbeFM are the fuckin MAN(s)
I will also Man up to full standalone as soon as I get it to a comfortably tuned level.

In the wiring diagrams of the Mazda factory service manual. http://www.madracki.com/miata/wiring.html

But here:

http://img31.picoodle.com/img/img31/...0m_c68fa73.gif

so what da issue been?

FYI I will probably be selling my '99 BEGI-S intake pipes very soon. They are in excellent condition, and already tapped for the AIT sensor. You can delete the pipes from the S kit and save some money.

OK thread jack over

The major problem was that he was trying to do a COP conversion at the same time as a MS conversion. The COPs were ones that I'd not seen previously, and they were either damaged or mis-wired, because any time you plugged one in (even with the MS out of the car) the 15A engine fuse immediately popped. We yanked them out and put the stock coils back on, and that fixed that.

I went through the ECU wiring pretty carefully (or at least, as carefully as a person can while standing on his head for three hours under the baking sun in a flat black car on a 100° day, watching other people drink his beer) and noticed one other abnormality. He used the piece of shielded coaxial wire that came with the MS pigtail for the CKP input as per your writeup, with the center conductor at DB-37 pin 24 and the shield at pin 2.

On the other end of that cable however, the shield was spliced into a wire of the factory ECU harness. My memory is hazy, but I believe it was a green/orange wire which we determined to be pin 2K- goes to the instrument cluster and the diag connector. I'm pretty sure it's the tach wire. So that wire was being grounded through the MS. Pulled it.

Anyway, the car starts and runs, though it's quite rough. Without a wideband it's hard to know where we are, and by the time we got to that point we were all pretty tired and just happy to see it running at all. For some reason, even though the O2 wire appeared to be connected I didn't seem to be getting a reading from it. Ignored that since a wideband is in the plan.

Also, I seem to recall that the MAP read a bit high- like 40-50kPa at what passed for idle. TeamPlur- if you're reading this, check very thoroughly for vacuum leaks on that line, and also tell me where on the manifold it connects, I forgot to check.

While trying to figure this out, Abe pointed out that we had no idea what the stock ECU was trying to do with the IAC valve- aargh! One of the frustrations of a parallel install.

parallel installs are badass.

If I wanted to do a parallel install on a '99, using the stock sensors, which parts would I need to order from DIY? I'm tempted to give this a shot. I'd use a Boomslang harness to simplify things.

Thanks

must read my FAQ you shall.

I read the one located here:

https://www.miataturbo.net/forum/showthread.php?t=13676

If I want to run MS-II, I'll just need to substitute This
Rather than This. Correct?

basically. modding it for inputs will be different, and im sure abe can help out...