Page 1 of 4

Megasquirt DIYPNP

Posted: Wed Aug 19, 2009 7:28 pm
by n2x4
Not sure if anyone's heard yet but the guys over at www.diyautotune.com released a standalone system that plugs into our factory harness. You've still got to build it and pin it out, but it's a good start!
We'd use the DIYPNP N76 model. Price is $460 for an unassembled unit (assembled aren't currently available).
Image

http://diyautotune.com/diypnp/index.html

If anyone is local in the Atlanta area, they're looking for a test car. I've already offered trailering any of my 3 vehicles down to them but they want someone closer at the moment.

It shows a lot of promise - unfortunately there's still a lot of development work for it to be installed in the Legacy, but it's got to start somewhere!

Posted: Wed Aug 19, 2009 8:38 pm
by gijonas
Yes!

Posted: Thu Aug 20, 2009 6:29 am
by epicfail
The factory Subaru 6/7 ignition system has already been made to work w/ the MS2extra software. It can be done for significantly less monies than the pnp kit, but pnp is easier, i suppose.
Also, a 36-2-2-2 wheel can be used in place of the factory 6-tooth crank wheel for better resolution and control.

Posted: Thu Aug 20, 2009 3:44 pm
by BXSS
Yey!

Posted: Wed Sep 09, 2009 3:03 am
by n2x4
Small update - I've found a local expert to help me get the ball rolling. I've placed an order for the DIYPNP kit, now it's time to wait!

Posted: Wed Sep 09, 2009 3:09 am
by kimokalihi
Awesome!

Posted: Wed Sep 09, 2009 4:39 am
by 93forestpearl
Does that use the cam trigger as well?

Posted: Wed Sep 09, 2009 6:40 am
by AWD_addict
Anyone know where to get a 76 pin connector and that board it attaches to?

That would be handy for those of us who bought MS kits before this came out. :roll:

Posted: Wed Sep 09, 2009 1:25 pm
by n2x4
93forestpearl wrote:Does that use the cam trigger as well?
I believe it does - http://www.msextra.com/ms2extra/MS2-Extra_Subaru.htm
AWD_addict wrote:Anyone know where to get a 76 pin connector and that board it attaches to?
I'd contact DIYAutoTune - the board comes unassembled, I imagine they'd sell the connector separately.

Posted: Fri Sep 11, 2009 4:06 pm
by GodSquadMandrake
Your wiring harness is the least of your worries when it comes to one of these, this isn't going to make Megasquirt plug and play by any means. Megasquirt is the furthest thing from plug and play. I've built one and run one on my VW. Let's put it this way... to change some programming options you need to solder jumpers. That's a long way off from something like Greddy Emanage Ultimate. Just my input before someone goes off the deep end and buys one of these thinking it will be easy.

Posted: Wed Sep 23, 2009 10:02 pm
by n2x4
Small Update:

Started assembling the components and mapping out the ECU connectors between MS and the factory harness.

I'll be using the MAF wires to control the MAP and IAT sensors. I won't be using the CPS at the moment (the megasquirt can control it, but it's the least of my worries ATM).

Currently debating on my IAC solution. I'm not sure what kind of valve Subaru used from the factory so I need to get that worked out so I can use it correctly.

I've also been debating on substituting a TB from a 1.8L with the built in IAC to clean things up a little.

Once the board is assembled, I can start to test things and see how it goes! The Microsquirt is really impressive, for a minimalistic install, you could run an entire car off of it.

Posted: Thu Sep 24, 2009 4:19 am
by AWD_addict
n2x4 wrote:I'd contact DIYAutoTune - the board comes unassembled, I imagine they'd sell the connector separately.
I did, they won't sell it separately. Apparently it's because of the way they order parts. It's a strange business that won't exchange parts for money. :smt101

Posted: Sun Oct 04, 2009 2:40 am
by n2x4
Progress began this weekend:
Image

Image

Image

Posted: Wed Oct 14, 2009 4:34 am
by 94legacy2.2
WOW lots of jumper wires

Sent you a PM on some info you may need.



To be honest the PnP is alot more work then needed right now. I'd let someone else do the testing on the PnP first. Thats just my option because I was the first to actually test out the 6/7 wheel and got it to work on a car instead of a stim.






Yes it reads the Cam sensor for the 6/7 wheel but the 36-2-2-2 doesnt use a cam sensor.

Posted: Fri Oct 16, 2009 2:29 pm
by n2x4
^ Thanks for the tips.

Update

Got the car to start and run last night. Few issues to clear up:
  • TPS wiring. The factory sensor goes from 5v to 0v, and megasquirt expects 0v to 5v. Due to some silly wiring I did when I swapped the ej22t into my car, we're unable to flip the wires to make it read 0v-5v. I can either dive into the harness to fix my wiring, or edit the megasquirt code to read backwards.
  • Coolant temp sensor. It's really hard to find enough information on the resistance values of the factory sensor. I tried to go off of the graph in the FSM and it's not quite correct yet.
  • IAT sensor. I need to run the air temp sensor somewhere in my car post intercooler.
After that, it's just a matter of tuning!

Posted: Fri Oct 16, 2009 2:39 pm
by 94legacy2.2
For the coolant, just ditch the subaru coolant sensor and use a GM sensor

TPS, cant you just swap the wires at the sensor in the plug? just remove the pin and switch them around


Congrats on getting the car to run

Posted: Fri Oct 16, 2009 3:50 pm
by n2x4
94legacy2.2 wrote:For the coolant, just ditch the subaru coolant sensor and use a GM sensor

TPS, cant you just swap the wires at the sensor in the plug? just remove the pin and switch them around


Congrats on getting the car to run
The goal of this setup is to get it to run on 100% factory setup, so I'm going to try and stick it out with the factory coolant temp. I've got a few other resistance values to try and get working.

Can't swap the TPS at the moment on my setup, The engine is actualy in a 1995 Impreza. I swapped the harness over and had to change a few things to address the difference in TPS wiring between the two cars.

It was very satisfying to hear the car run last night, I can't wait to start tuning.

Posted: Sun Oct 18, 2009 10:42 pm
by Legacy777
The stock coolant temp sensor uses a standard Bosch NTC curve.

TPS, swapping wires probably will not work. The actual resistance inside the TPS is setup this way. I don't believe changing wires will do anything.

Does the MS allow you to calibrate the TPS? Link has a throttle calibration, and it automatically calibrates it for the reverse resistance pattern.

Posted: Sun Oct 18, 2009 10:46 pm
by 94legacy2.2
Yes the MS lets you Calibrate the TPS.

Thinking about it I dont think you need to swap the wires. You just go to tools>calibrate tps> get current for throttle in neutral spot and then get current while at WOT.

Should give you a high number in the first box and then a low number in the bottom box. Save changes and see what happens.

Posted: Sun Oct 18, 2009 10:56 pm
by Legacy777
Yup, that's really all you should need to do if you can calibrate the TPS.

Posted: Mon Oct 19, 2009 3:08 am
by n2x4
Unfortunately, MS isn't coded to support throttles with voltage that drops. When you calibrate it in Tunerstudio or Megatune, you get an error stating that close throttle value must be lower than max.

Kinda dumb if you ask me for scenarios like this.

Posted: Mon Oct 19, 2009 4:00 am
by 94legacy2.2
hmmm didnt know that. Ive never been in the situation where the voltage was backwards.



cant it just be easy as you cut the ground and power wires on the TPS and swap them, reconnect so the POT (tps) reads normal for the MS?

Guess im not understanding why the wires can be swapped. Ive done it on my race car. 3 wire Tps, pin1 power, pin2 signal, pin3 ground

Posted: Mon Oct 19, 2009 1:48 pm
by n2x4
94legacy2.2 wrote: cant it just be easy as you cut the ground and power wires on the TPS and swap them, reconnect so the POT (tps) reads normal for the MS?
That would work yes, but when I did my wiring swap I tied the TPS signal ground into other signal grounds, so if I flip them, I'll be sending out voltage on the other signal grounds - not exactly a good idea.

That was a mistake on my part, when I wired the car up. Not a huge deal, I just have to run a separate signal ground and then I can flip them, either that or modify code to make the TPS work "backwards" as MS considers it to be and leaving the existing grounds alone.

Posted: Mon Oct 19, 2009 6:00 pm
by Legacy777
Other thing to note is that if you have an auto trans, the TCU will also need to see TPS voltage, so you can't swap wiring around.

Posted: Mon Oct 19, 2009 6:54 pm
by n2x4
Legacy777 wrote:Other thing to note is that if you have an auto trans, the TCU will also need to see TPS voltage, so you can't swap wiring around.
Good point Josh. Fortunately for me, that won't be an issue, but that's definitely something to consider for those with a slushbox.