Megasquirt DIYPNP

[94legacy2.2]

so whats the word on tihs

[n2x4]

I've made some progress - IAT is installed in the intercooler end tank, and I've given up on the TPS for now and will just run with the MAP based acceleration just to start tuning until the snow flies.

Still haven't nailed the values for the coolant temp sensor, but it's definitely close.

Current issue right now is the car won't rev past 4K rpm. Seems like a lot of people have experienced this issue. I was hoping there was noise on the crank signal, so I tried a 470OHM resistor without luck. Also tried a 300OHM resistor with the same results. Hooking up a scope to watch the signal didn't show anything unusual either. It was rock solid until 4K when the entire RPM signal drops out.

So it runs, but still needs some things to be figured out. Just takes time!

[fastwagn]

have you had the chance or any luck with your 4k breakup? which crank tone wheel did you end up using? are you staying factory ignition with the stock transistor box on firewall or using the ms2/e cop setup?

[impreza_GC8]

I'm subscribing to this thread. I was about to pull the trigger on that very same MS unit, I'm a bit disappointed to see that it requires a lot more work than the "plug n play" title suggests. Hopefully after following this thread and reading what you have to say I will follow in your footsteps. My goal was to make it work as a stock setup as well, in place of the factory ECU, with the eventual goal of switching to speed density. Keep us posted please!

[n2x4]

No update yet, project was put on hold for the winter. I just changed the oil in the car and have it ready to be finished.

Still dealing with the 4k RPM issue, though at this point we believe we have the resistor issue figured out. I'm currently using all stock ignition and tone wheels. Pretty confident that if I had used the 36tooth wheel I'd already be running.

The goal is still to be as plug and play as possible. I've reused extra factory connectors to hook up additional sensors that the MS requires. By the end of the month I should have a success story to report back with.

[FoundSoul]

Jerry from DIYAutoTune.com here. If you're ready to pick this back up let us know Neal, we have made some improvements in the product to make difficult VR setups like the Subaru is notorious for having MUCH easier. The board you have should work, but we've added a new circuit to the current models to make it even easier.

As for the DIYPNP being plug-n-play, there's definitely a reason DIY comes before PNP in the name. We offer a few full assembled PNP's too under the name MegaSquirt PNP, and those just buy, install, and tune/drive. The DIYPNP is available for a massive number of vehicles, but is aimed at the DIYer who will able to put a bit of work in and build their own PNP ECU. That said Neal's car has been much more troublesome that most, the Subie VR signal is very noisy and difficult to decode cleanly without purpose-built hardware. The new DIYPNP mainboard (v1.5) is much better at handling this noise and to my knowledge we haven't found anything it doesn't work on so far.

[sleepinsuby]

I am extremely interested in this for my ej22t/2.5i hybrid build. Your saying that this company is offering a pnp set up now or just the diypnp? and if you are offing the pnp whats the price ?

[impreza_GC8]

DIYPNP.com is the website. They have vehicle-specific PNP kits assembled for around $700 if I recall correctly. I still think the $420 unassembled Microsquirt kit is by far the best deal, you solder it up yourself and it plugs right in. After that is where I wonder what further work is required. Jerry, thanks for stopping in to comment, I want you to know that I have been on your website multiple times ready to buy your N76 Microsquirt kit but each time can't bring myself to do it. If you could clear up what is needed to actually make the ECU "plug n play" (aside from the assembly) that would persuade me to pull the trigger.

[FoundSoul]

Really it comes down to the assembly and the jumper wiring to match your cars harness pinout to the mainboard. This all happens internally, so basically there are three PCBs inside the case. The Mainboard, which has 99% of all circuitry installed on it (by the builder) including the MicroSquirt Module (which is the second PCB as it's a daughterboard). The final board is the connector board which hosts the vehicle specific connector, and has all of the signals broken out to thru holes.

So once the core assembly is completed you have the mainboard and the connector board.

The mainboard has all of the signals/power and other i/o brought out to thru holes right on the edge of the board.

The connector board has all of the harness connector pins broken out to thru holes as well.

And then you connect the dots.

Start with grounds. Run a jumper wire from the ground pins on the mainboard, to the ground pins on the connectorboard (referencing your wiring diagram).

Do the same for 12v power. Another jumper wire.

Now plug it in and test. Does it power on? Can you connect to it with TunerStudio? Great! Next step.

Run the IAT signal jumper wire. Plug in and test. You have an IAT signal now? Great! Next step.

Run the CLT signal jumper wire. Plug in and test. You have an CLT signal now? Great! Next step.

You get the picture, IAT/CLT/O2/Crank/Cam/etc. You run a jumper wire for each signal to match the pinout of your car. Sortof like building a mini harness, just inside the DIYPNP case, allowing you then to use your stock harness and not have to rewire your car.

I like to suggest people do it one wire at a time if they're unsure of themselves, because then if there is a problem you catch it early. You can just carefully research things and wire them all up at the same time and test it once assembled, but if there is a problem you will have more rework to do to correct it. That's up to you though. We wire them all up at once here, but we've done a few of them .

Note that we are working towards making these even easier to implement, eliminating most of the jumper wiring. That's not happening overnight though, and really we'll need a test car to make it happen.

That said, is there anyone that's interested in running a DIYPNP but would like us to do the install for them? Free labor for the assembly and installation? We'll be glad to do it if it's a car we haven't documented yet, and you'll be helping to make the install easier for all your buddies here, as we'll supply a full pinout chart (for the jumper wires) and a base map to get the car fired up easy. Someone bring us a car!

[fastwagn]

atlanta area? or....

you guys installed an ms2 on an 87 rx with my friend/fellow subaru tech will. i'd be interested, but have some loose ends and a few track days this summer, plus finishing two other projects. maybe nov/dec? worth your wait? although i must say i would rather do the install myself with documentation/guidance at your shop if that helps...i would be more than willing to let you do the somewhat tedious soldering steps

that said, would you tune? and can i bring my tuner for some guidance? oops, just saw, base map will be perfect!

[FoundSoul]

Yep, Atlanta area. Actually Suwanee just NE of ATL.

If we haven't found something by then we'd be interested. But I thnk if I put a feeler out there we very likely will have it documented for you by then.

Tell Will I said hey...

[impreza_GC8]

I'm interested. How long would you need the car for?

[FoundSoul]

Usually we plan for two weeks, sometimes we need it less and sometimes a bit more, but we stay in touch with you on it.

[n2x4]

Well, it's officially alive. A 10k resistor in line with the cam signal fixed my rev issue. We still need to sort out proper fueling. At the moment it will rev to about 6200 RPM, but then runs out of fuel. A base tune will make the car drivable and once we shake out the bugs, I can consider it a complete success and share some of our spreadsheet data!

Amazing how one little 10 cent radioshack piece can change the game. The subaru cam signal had an output voltage that was more than the MS could deal with that got worse at higher RPM. That's why it would drop out at 4K. This brought the signal down to make the magic happen!

Jerry - Good to see you on our boards. Justin Gray has been the brains behind this MS project.

[fastwagn]

that is some great progress!

[Alphius]

Awesome! This is great. I have a MegaSquirted Camaro and I've been watching the Subaru MS progress closely. Nobody really has any good information, although a couple claim to have made it work. The more information we have, the better the community will be. Myself, I have no need for it right now but it's good to know the option will be available to me since I already know how to tune the MS system and it's a very good cost-effective option.

[impreza_GC8]

Great! Please post up as much information as you possibly can, I'll be following in your footsteps.

[93forestpearl]

If this can turn into at least a wire-in affair, I expect to see a lot of Subarus running MS's in the next few years. I shied away because I didn't want to change cam angle and crank angle schemes.

[FoundSoul]

Soon as we get one of your cars in here to test on we'll provide the pinout and startup map and you'll have a paint-by-numbers style assembly/jumpering using the DIYPNP.

[impreza_GC8]

I'm very tempted to offer you my car but I don't think it will be the best guinea pig. Although it is running an EJ22T ECU, its not a 1991-1994 Legacy turbo, its a '97 Outback with a hybrid setup that just uses an EJ22T ECU to run it. I have a merged Legacy turbo engine harness.

[FoundSoul]

Yeah that may not be the best fit. In order to help the largest number of people it would be best if it was a near stock car, or at least was running the original motor and electronics. If we sort the system for those guys, then you others with the wilder builds/swaps can adapt what works on the stock car to your own much the way you did with the factory ECU. In some cases no changes will be needed, in others they may.

[Tommio RS]

Hmmm.
This Megasquirt is very very interesting, can this ecu system totally bypass the factory ecu and still have the same driving capabilities?

In saying that.

Can one run a complete MS system to run everything in a legacy turbo? So the factory ecu is sitting on a bench then.

Here is the ecu pinout of a 90-94 legacy.

Link:

http://www.surrealmirage.com/vrg3/ecupins/

Im after this ecu tuning to get the best power with my 550cc injectors with a VF39 and a JECS maf sensor.

[FoundSoul]

The MegaSquirt, and the DIYPNP, are full standalone engine management systems for full control of all aspects of engine management in a racing environment, and do not require the stock ECU (set it on a bench). They do not address emissions control devices for example and are not legal for use in polution controlled vehicles in most countries. They give you massive amounts of control over your motor though, allowing you to perfect your fuel and ignition advance curves and add new capabilities to your vehicle as well, custom ignition systems, nitrous, boost control, adjustable rev limits, launch control, flat shift, and alot more....

Your injectors will be fine, you will want to use a resistor pack or Peak-N-Hold box. The maf sensor could be used, but most of our customers use the internal map sensor for speed density and that's what i'd recommend.

[Tommio RS]

Hmmm So everything but emissions A. I sure dont care about emission. Im NEVER going to sell my legacy and the emission system is really simple in a OBD1 car to my knowledge.

So all i need to do is buy a DIYPNP ecu/ the nippon denso 76 pin one. Figure out the pinout of the MS because we all have the factory ecu pin out and Boom tunning time!

I like how this is going. Sounds better than the ecu chip crap that has been around.

As for what the MS ecu CANT do that the factory one can do is:


Canister purge control and emission stuff
The MIL and everything else attached to that ball of wax
AC Stuffs
Transmission stuffs like park switch and neutral switch AT only

Not sure about the vss tho can megasquirt do that??

Feel free to file this thread with the maximum amount of info about how to convert to MS.

[n2x4]

So all i need to do is buy a DIYPNP ecu/ the nippon denso 76 pin one. Figure out the pinout of the MS because we all have the factory ecu pin out and Boom tunning time!

You're making it sound much simpler than it really is, but essentially that's the idea. You'll also need to build a circuit to control the IAC, unless the newer revision of the PNP board includes that now.

As for what the MS ecu CANT do that the factory one can do is:


Canister purge control and emission stuff
The MIL and everything else attached to that ball of wax
AC Stuffs
Transmission stuffs like park switch and neutral switch AT only

Not sure about the vss tho can megasquirt do that??

Feel free to file this thread with the maximum amount of info about how to convert to MS.

Megasquirt can run the purge, you just have to build the circuit to run it.

The MIL is nothing more than a yellow light switched on by the ECU. It's just a crude view into the "mind" of the ecu. You can use megasquirt to trigger the MIL if you want it to, for whatever you want it to. As far as diagnostic use? No point, that's what the laptop's for.

AC can work as well. The factory ecu just bumps up the idle if the compressor kicks on. Run the AC wire output to megasquirt. When it gets the signal, make it bump the idle.

You could make the auto trans work. Neutral switch is another condition related to idle. Park switch is so the car starts. Both easy to account for if you know what they do.

Megasquirt doesn't require VSS to run, I haven't looked at the auto wire schematic in a while, but I'm pretty sure the TCM reads the VSS signal in line with the factory ecu, so you shouldn't need the ECU to provide that input to the TCM.


There are a few megasquirt ECU's running in a Subaru. All the answers are out there, it's just dealing with them is the challenging part!