MS3 with MS3X 96-97 Build
 

I'm building a MS3 with MS3X to put into a Westfield (like WestfieldMX5 has) that has a 1997 Miata engine in it. The engine is stock for now but I plan to add a MSM turbo soon which is why I bought the MS3. Since I also have a 1996 Miata that is completely stock I'm planning on putting the MS3 into that first to learn how to use it and tune it on the road while I finish building the Westfield.

Thanks to WestfieldMX5's webpage and Braineack's posts here in the forum I've put the board together. I'm using the VR input for the crank and the MS3X "CAM IN" (pin 32) for the cam as per Westfield MX5's instructions. I like the precision of using the MAX9926U chip instead for these inputs but I'll leave that for later.

I finished building the board, confirmed it could power up, loaded firmware on it, and confirmed operation of the some of the sensors using a JimStim and Tuner Studio.

I now need to build the harness which I'm going to do using the diybob pcb and I also need to do the "MS3X idle circuit modification". Is there anything else that needs to be done? I will also be using a wideband O2 sensor.

I plan to wire the MS3 to the 96-97 harness as shown below. Can somebody please confirm that this is correct? Is there anything that I'm missing or is plainly wrong?

Also, can somebody supply me a base .msq for a 96-97? I just need something to get me started, get the engine started, and doesn't blow anything up.

MS3 -- 96-97 Harness:
1 GND -- 3O SENSOR GROUND
2 GND -- 4A SENSOR GROUND
3 SPR1
4 SPR2
5 SPR3
6 SPR4
7 GND -- 4C GND
8 GND -- 4D GND
9 GND -- 1O GND
10-19 GND -- ENG GROUND
20 MAT -- 3K MAF/IAT
21 CLT -- 3G CTS
22 TPS -- 3F TPS
23 O2 -- WIDEBAND O2 (#4)
24 TACHIN -- 4F CAM POS SEN
25 IAC1A
26 VREF -- 3I 5VREF
27 IAC1B
28 12 RAW -- 4B 12V
29 IAC2A
30 IDL
31 IAC2B
32 INJ-1
33 INJ-1
34 INJ-2
35 INJ-2
36 IG_OUT
37 FP1 -- 1U FUEL PUMP


MS3X -- 96-97 Harness:
1 INJ G -- 1G A/C RELAY
2 GND -- ENG GND
3 GND -- ENG GND
4 INJ F -- 1A COOLING FAN
5 FLEX
6 BOOST
7 INJ E
8 GND -- ENG GND
9 IDLE -- 4Q IAC VALVE
10 INJ D -- 4V FI-2
11 LAUNCH IN -- 1L CLUTCH SWITCH
12 GND -- ENG GND
13 INJ C -- 4X FI-4
14 SPK A -- 4N COIL 1&4
15 SPK C
16 INJ B -- 4W FI-3
17 GND -- ENG GND
18 SPK G
19 INJ A -- 4U FI-1
20 INJ H -- 1B CONDENSER FAN
21 SPARE ADC
22 EGO2
23 EXT_MAP
24 NITROUS1
25 NITROUS2
26 TACHO -- 4L TACH
27 WT
28 TBLSW IN -- 1K A/C SWITCH
29 NITROUS IN
30 DATALOG IN
31 PT4
32 CAM_IN -- 4G CAM POS SEN
33 SPK B -- 4R COIL 2&3
34 SPK D
35 SPK E
36 SPK F
37 SPK H

You really don't need the MAX9926U, it's a waste of time.
The idle mod is merely one diode.
Other than that, you don't need anything else. Alternator circuit is not needed.
Haven't checked your wiring table, but there's one on my site that you can consult. There might be a msq as well.

I have checked your site in regards to the wiring table and it looks right. I just wanted somebody to double check it before I wired up the harness.

There is a link on your site that points to the 96-97 base map but it is not working. I would really appreciate it if you could get that base map up. Thanks!

94-95 will work fine as well.

I tried downloading it from your site but the link you have to the 94-95 base map points to a jpg and not the msq.

Can I use the DIYPNP one as a starting point without damaging anything?

I fixed the injector firing order. I had the injectors connected to the MS3X like this before:

Inj A - Inj 1
Inj B - Inj 2
Inj C - Inj 3
Inj D - Inj 4

I thought that the firing order was set in the "Engine and Sequential Settings" but that is not the case. According to the MSExtra manual in sequential or semi-sequential mode, the outputs always fire in sequence A,B,C so the firing order must be set in the wiring.

Apparently, the "Firing Order" settings in the software just make sure the fuel trim is applied to the correct channel.

Correct. Outputs must be wired in firing order.

this.


use the 94-95 basemap on Frank's site for your 96-97 basemap, just make sure all the ins/outs match up to how you built your harness.

Can you post or send me that basemap? The link to it on Frank's website is not working.

Thanks

change .jpg to .msq and see if that works. I think he messed up the link. :)

I already tried that. I even tried guessing the name of the file to get it off of his dropbox but that didn't work either. lol

see email.

I didn't get it. I sent you a PM with my email address.

never, i cant the find the email i sent frank with that map.

Just noticed it's a wiring diagram instead of an msq. I'll see if I can dig one up somewhere.
edit: found it :), link is working now.

Got it! Thanks

Thanks again for the base map. The car is up and running.

I had an issue with the #3 ECU harness. It wasn't making a good connection and all the sensors were working sporadically. I crimped a little bit the stock wiring on the harness and things improved. Everything seemed to work except for the coolant sensor which would go back and forth from working and 90 degrees. I then cleaned all the grounds but still had the same problem. I decided to replace the coolant sensor and that fixed it. I guess the bad harness connection finished off the sensor.

The car still wouldn't start but after taking a look at the composite logger I noticed that the CAM and Crank inputs were inverted (I updated the wiring map in my first post for anybody that might run across it). After I fixed that the car started right up.

Using the .msq from Frank, I had to bump up the idle fuel VE map. From there I locked the timing and set car's timing at 10 degrees. I also tried to set the latency to compensate for timing lag at high revs but I didn't notice much of a difference. Frank's map was set at 21 usec and I put it 14 usec. But again I didn't notice much of a difference if I set it at 0 or 50 usec.

I then used the DIYPNP spark map and Braineack's AFR table that he posted. From there I started VEAL and car runs pretty good.

I need to play with the idle settings when I turn on the A/C next because when I do the car runs lean and turns off.

congrats, nice going.