Hold my hand while I wire up this MS2 3.57 to my friend's 91
#1
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A friend of mine asked me to wire up the MS2 he got as part of a T25 kit he got for his 91. I used these pages for reference:
Megasquirt 2 Harness Assembly - Miata Turbo FAQ
Megasquirt 2 - External wiring layouts
http://www.miata.net/garage/ECU%20Pi...90-93%20MT.pdf
I bought a connector from DIYAutotune, and plan on making an adapter harness for the MS2 to make it "plug-n-play-ish."
Here's my work-in-progress paint-tacular wiring diagram. Tell me where I fucked up before I start soldering. What should I do with the TPS? I told him he'll need some sort of variable tps, and mentioned the BMW ones. Is there an ideal place in the stock harness to wire it up, or should I just run new wire?
![](https://www.miataturbo.net/attachments/megasquirt-18/97309-hold-my-hand-while-i-wire-up-ms2-3-57-my-friends-91-yckcdpj.jpg?dateline=1386876852)
Here's the car and turbo setup to keep you interested:
![](https://www.miataturbo.net/attachments/megasquirt-18/97310-hold-my-hand-while-i-wire-up-ms2-3-57-my-friends-91-yzo7tao.jpg?dateline=1386876852)
(Not the turbo going on)
![](https://www.miataturbo.net/attachments/megasquirt-18/97311-hold-my-hand-while-i-wire-up-ms2-3-57-my-friends-91-rckp3of.jpg?dateline=1386876852)
(that's more like it)
Megasquirt 2 Harness Assembly - Miata Turbo FAQ
Megasquirt 2 - External wiring layouts
http://www.miata.net/garage/ECU%20Pi...90-93%20MT.pdf
I bought a connector from DIYAutotune, and plan on making an adapter harness for the MS2 to make it "plug-n-play-ish."
Here's my work-in-progress paint-tacular wiring diagram. Tell me where I fucked up before I start soldering. What should I do with the TPS? I told him he'll need some sort of variable tps, and mentioned the BMW ones. Is there an ideal place in the stock harness to wire it up, or should I just run new wire?
![](https://www.miataturbo.net/attachments/megasquirt-18/97309-hold-my-hand-while-i-wire-up-ms2-3-57-my-friends-91-yckcdpj.jpg?dateline=1386876852)
Here's the car and turbo setup to keep you interested:
![](https://www.miataturbo.net/attachments/megasquirt-18/97310-hold-my-hand-while-i-wire-up-ms2-3-57-my-friends-91-yzo7tao.jpg?dateline=1386876852)
(Not the turbo going on)
![](https://www.miataturbo.net/attachments/megasquirt-18/97311-hold-my-hand-while-i-wire-up-ms2-3-57-my-friends-91-rckp3of.jpg?dateline=1386876852)
(that's more like it)
#2
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So is my wiring diagram just so awesome that everyone who saw it went into a coma? I still have zero idea if this is correct or if I'm completely off.
Unless someone objects, I'll start soldering it tonight.
Does anyone have the missing images from Megasquirt 2 Harness Assembly - Miata Turbo FAQ ? The top one in particular is the one I (and at least 1 other member who PMed me) am looking for.
Unless someone objects, I'll start soldering it tonight.
Does anyone have the missing images from Megasquirt 2 Harness Assembly - Miata Turbo FAQ ? The top one in particular is the one I (and at least 1 other member who PMed me) am looking for.
#5
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The main reason I did that is because the only 2 wiring diagrams I could find seem to contradict each other on the pinout of the 1.6 ECU socket. That or I'm reading them wrong (more likely). From the M.net PDF, the injectors appear to go on the 4th pin from the left (top and bottom), but according to the MT wiki, they go on the 3rd from the left. So which is it?
Either way, that's why I made it with the actual ECU connector rather than a drawing. I want to be reasonably certain I've at least got the right pins before I start soldering.
Also I know you're jealous of my mad paint.net skillzzz
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