MSII on MK1 (4/2 CAS)
 

Right I've spent the last couple of days updating my trusty MSI to MSII

Pretty much followed what Braineak did here with his build, (good timing!). I.e. pullups direct to the CPU. I didn't swop R12 for a 470 resistor tho, I left teh 390 in place as I didn't have any to hand.

it all works perfectly on the JimStim, but bang it on the car and I get intermittant rpm, (see attached logs).

Any ideas?!?

Oh all the wiring from the DB37 to the car's harness is idential, I've touched nothing! so discount any wiring issues.

Cheers ears!

What wiring diagram did you follow with the input circuit? Do you have both triggers wired up? Check MS2-Extra Miata 4g63 Manual

When I did my input circuits i used that wiring diagram, then i used Joe's improved spark for output, with the exception that i ran the second out through a spare pin. It seemed to work for me. Check you settings for the ms2 and make sure they match that page.

I'll have my unit on my car tomorrow for the first time myself. So I'll let you know how mine runs tomorrow, I just spent all morning converting my msq over.


If you don't swap the R12, you can at least add a 100ohm on the 5v pull-up to bring it closer to 470ohms. like this one floating around:

http://www.msextra.com/ms2extra/Igni..._In_V3_NEW.GIF



Did you install the .1uF cap on the daughterboard to filter the 2nd trigger signal?

Yup added the cap, cheers for the replies.

I've finally sorted it. I swopped to the MSII suggested circuit with an opto Isolator, no difference, (though the input on the JimStim was loads sharper. I'd reccomend building that circuit...)

In the end I realised that my ignition trigger was WAY off, despite me copying my MS1 settings, it was almost 180deg out.

The only way I could get it to work was by swopping the leads around on the coilpacks. Once I did that it fired up pretty much straight away. I really don't get why though as I've not touched the output circuits nor the output wiring....

Very impressed with the smoothness already, just need to dial everything in. I'd forgotton how much closed loop idle helps with Idle dip too... need to tune that soon!

Tomorrow I go to full sequential!

Cheers for the help all!

The PID idle stuff is bomb too. Use a very small P, a big I, and 0 D. 2-120-0 works well for me.

Now, who's setup up the PID stuff for boost control is what I wanna know. I have no clue what to put in for the gain % numbers.

next problem!

Drove home, (work on my car at the parents house/garage) hoping to get a few Datalogs and dial in the VE table.

Unfortunately it cuts out above 4.5k

Any ideas why it might do this?

log and .msq attached!

Haven't tried the boost stuff yet, but I think the approach is the same. It's all in the I. Start low and work up. Too little might not hit target, too much will overshoot and oscillate.

Do you have a small cap acting as a filter on the 2nd trigger? Might need to remove it.

I have got a 0.1 cap on the 2nd trigger.... hrm!

I *assumed* it'd be required as per the MS1's do.

Good point that, I'll post it on MSExtra too..

Brain, be curious as to how you get on tomrorrow with the cap in place!

do you have c30 and c12 removed?

I wont be able to get too far, because I don't have my timing light and I don't have the fan, ebc, and clutch inputs hooked up because I don't remember where they on my harness.. but I should be able to get around the block and see how it runs.

Ben,

Do you use the frequency extender board? just wondering if it's 100% required :)

My stock PCM is running the idle valve. That's a different story.

I would consider the extender board optional. You should be able to achieve decent idle control without it.

found a good read on the boost control: Megasquirt MSEXTRA and MS3EFI • View topic - Closed Loop boost (beginner to pro) log

C30 and C12 were never installed when I built the board years ago :)

Let us know if you encounter the same timing 'issue' I had, it's very odd, I'm not really sure why it happened.

I'd lend you my timing light, but it's probably not very economical ;)

actually, ill have my light...

Added a few new guages, specifically a lost sync guage and a clock guage to confirm whether I'm getting rests or a loss of sync.

I'm getting a loss of sync.

Now I'm at a loss of how to fix it! Just about to try removing the cap on the MSII daughtercard.

Added a few new guages, specifically a lost sync guage and a clock guage to confirm whether I'm getting rests or a loss of sync.

I'm getting a loss of sync.

Now I'm at a loss of how to fix it! Just about to try removing the cap on the MSII daughtercard.

Hi Brain,

I did - or do.

My big post about it at msextra.com is lost at the big forum crash.

But here is another good thread.
Megasquirt MSEXTRA and MS3EFI • View topic - Closed Loop boost (beginner to pro) log

EDIT: Whoops.. should have read further first.

Ken at msextra proposes to do like this:

First, turn off all I.
Second, Adjust P higher. Keep going higher until it gets close to your boost without overshooting (a little overshoot is OK here).

Once you get to this point, adjust the I term until the code will hold your target boost across the rev range.

Last, adjust the D term to get rid of any leftover overshoot, and to help with any oscillation that might pop up.

You should end up at something like my values -

P/I/D
105/48/150

I am not certain about the high D value - you probably won't need this so high.

And yes it is worth it - the cl boost works a charm with MS2.

Keep in mind that you need at least the 2.1.1 version of the firmware.

Greets

the 0.1uF cap on the MSII daughtercard was at fault for the loss of sync.