Serper3

iTrader: (3)

Time to install my Megasquirt II so there are a few things I want to
verify before I begin the install tomorrow. I have a 99 Miata that I am
going to run stand alone with the stock sensors. (Trigger input circuits
built by Abe, Abe is the man!)
First off, the harness has several wires that I have to solder or crimp
onto the stock wiring. I am kind of confused as to where these have to
go though.
I have a light purple wire marked o2, this goes to the signal for the
lc1..
I have a wire marked boost and another marked knockense so since I am
not doing electronic boost control yet and I don't have a knocksense I
can just tie this away safely..?
1. I have a wire marked iat.. this goes to the iat sensor I am putting
in.. how does it connect to the pigtail from the sensor?
2. I also have 2 red wires coming from the ecu connector, where do these
go? Is this power for the wideband?

3. Since I am taking the stock ecu out, I need to/can just take out the
stock o2 sensor and use the same bung for the lc1 wideband (until I go
turbo in a week or so)?
4. Where do I want to run the vacuum line from the ms map sensor? There
is one port right by the throttle body and another one on the intake
manifold farthest from the radiator side. And also in the future, can I
tee off one of these and run the other tee to my boost gauge and blow
off valve? Which ones are best to use for what?
5. For my current iat sensor install where is the best place on the stock rubber intake tubing to put the iat? For when I go turbo, I know the iat needs to go after the
intercooler, but more specifically where? I don't have the sensor now to look at, but
does it need to be drilled and tapped and the sensor screwed in? Can I drill a slightly larger hole and fit it in and jbweld it in place? What's the easiest thing to do here guys?
6. I am going to have to tune this thing... hopefully someone who has
done this before will be able to help, but is their a good site where I
can get some info on tunning etc.
7. When I check for timing, do I just make sure that the timing the ms
has for idle matches what the timing light shows?
Thanks a lot guys, I know this is a lot of questions but I just want to
make sure I don't really mess anything up bad.
Henry

maharashii

Since I just asked some similar questions, I'll take a stab at a few of these. I am by no means an expert, however. Keep in mind that I am doing an MSI parallel install in my NB.

Yes - the brown analog signal wire on the LC-1. Same wire you use if you're putting in an AFR gauge.

I dunno about EBC, but I'm leaving the knocksense wire disconnected as I do not have a knocksense either.

The GM IAT has two wires - orange (A) and black (B). I plan on running A to the IAT wire for the Megasquirt (pin 20). I imagine the other wire goes to ground, but I don't have confirmation on that.

In my '99, I got vacuum from the cruise control actuator with a tee, and ran the line through the firewall by poking a hole in the large rubber grommet on the driver's side. I did this for a vacuum gauge - I'm not running vacuum to the MS.

I was told to just drop it in the stock airbox, but I haven't explored this yet.

Serper3

iTrader: (3)

Very good info. Thanks a ton! If we could just get some confirmation that would be great!
As far as putting the iat in the air box... I bought the with a racing beat air intake so their no box... Wouldn't the air be similar temp though regardless of the box? Can I just secure it to the intake itself? I might try to sell the racing beat today and in that case, just put the sensor in the air box secure it and close the box?
But if I don't or can't get the stock air box... Where should I put it?

patsmx5

iTrader: (16)

This is V3.0 but I 'think' it's all the same.
Link if IMG tags don't work: http://www.megamanual.com/ms2/v3ext_wiring.gif



That should answer 1&2
3-yes, but read the installation papers with your LC-1 on how to build a heatsink.
4- Yes to all


5

6- Look around miataturbo.net in the Megasquirt forum. Also read through the Megamanual. But In short once all the electronics are working tuning is easy. Make a datalog then run it through MLV and it will make adjustments.

7. yes

AbeFM

iTrader: (3)

Hey! Glad to hear you got it - I'm as anxious as you are to see this thing up and running. Let me see which of these questions I can tackle.

Unnumbered:
Yeah - the O2 goes to the LC-1, I like soldering, but you might get more opinions on that. Mine are crimped so I can remove the harness from the car.

The boost wire could technically be used to drive anything, I would get a piece of shrink tube, let it hang past the end and shrink it on, to somewhat better protect it. It's just a ground, so it won't hurt even if it DOES short somewhere - but it's bad practice.

The knocksense is an input, so you'd want to be sure to insulate it and stuff it somewhere safe. Grounding it would be ideal. Probably you can leave those inside the wire-wrap to keep them safe.

1) Yes, this goes to the GM sensor. Hmmm, actually, I'm not sure where the 5V that goes to it comes from! I guess I'll check my car.
Edit: Pat pointed out that I'd given him the same bad advice! You ground the other side of that sensor, which I imagine I will see when I check my car.

2) I wrote something on the wires to tell you what they are. MAke sure you verify this, but I believe they are for the mopar altenator control box, and labeled as "green" and "blue" so you know.

3) Sure, you can use the OEM location for the wideband if you're not running boost. They can overheat, so the further back the better. I believe you want to be ahead of the cat though!

4) I like the port in the back. I've seen this argued endlessly. :-) I would run the boost gauge off another port, and the BOV off another if you can find it - but definitely keep the MAP on it's own line to give it the least polluted reading. Again, you'll get other opinions on this. I'd probably put the BOV signal near the front.

5) I guess put it where the stock one goes, near the air flow sensor. Actually, I think it's shoved in the airbox. Anywhere it fine on a NA setup, really. You could put a nut on the back of the sensor, but if it comes loose it could get sucked into the motor: Bad idea. In the past, even with thin IC piping, I've had luck tapping it. It's not under much force.

6) Maybe someone has some suggestions, but GET YOUR LC-1 SET UP ASAP. If you're not making much power, things are pretty forgiving.

7) Yes. There's a "trigger wizard" which also will help with that. Easiest thing it to set timing from "table" to "fixed", set it for 10* and see what it is with the timing light. With stock sesnors it should be pretty close to what I sent you. Also, once it's set about right, turn fuel back on (you can do the early testing with no fuel) and rev it a bit and make sure the timing doesn't change with RPM.

Keep the questions coming - lots of people here have experience with running the MS.

AbeFM

iTrader: (3)

Really, not to be a dick here, but wait till you get yours up and running. I've skimmed your other threads and it seems you still have a few misconceptions about engine management and electricity in general. If he sucks his IAT sensor through his engine, are you going to be replacing it for him? Are you suggesting he runs his MAF? The LC-1 has two outputs, he doesn't have to use the brown wire. etc etc....

Serper3

iTrader: (3)

Do I have to disconnect the ignitors? I have read this some where in the past.. can someone explain please what needs to be done? Just pull the plug wires off? Or is this not necessary?

I am still not really sure how I will mount that iac before I go turbo with the stock rubber intake.. I have a racing beatintake but its kinda like a ram air setup so their is no where I can insert it. Since the car is na can I put in next to or on the air filter since its exposed?
Thanks guys u guys are the best!

patsmx5

iTrader: (16)

Ok I did all that and didn't even get a thankyou... SEARCH! All your question have been answered. It's one thing when you're building and get hung up and need an answer ASAP, but you are just being lazy and hoping everyone will spoon feed you.

Joe Perez

iTrader: (8)

When the CPU is inactive (as is the case with an unprogrammed CPU or one which is in the process of being reflashed) then the two ignition outputs go high. If the igniter and coils are connected during this time, this will cause the coil primaries to conduction continuously. This condition (continuous operation of the coil primary) generally results in the destruction of the coils or the igniter due to overheating.

Thus, any time the CPU is inactive (ie: while loading new code) the ignition coils must be disconnected. Not the plug wires, those are on the secondary. You must disconnect the primary. On the '90-'93, this means unplugging the igniter. On the '94+, remove the two 3 or 4 pin connectors from the coils.

maharashii

Fine, but I don't really understand your criticisms here.

No, of course not, but it would be common sense to secure it somehow. I wasn't suggesting that he leave it flopping around.

No, I suppose he could use the yellow or the brown analog output. That's not a misconception, just me being incomplete. It's all in the manual anyway. My apologies for the confusion.

patsmx5

iTrader: (16)

Fixed.

Serper3

iTrader: (3)

Uhh.. What r u talking about? I did say thanks.. It was the last line in my post.
I am not being lazy. I have been reading all the time but for most of my questions, I was just making sure I am on track.
Its also kinda hard to research on my blackberry at work and during school. I am trying to get all this stuff done tmrw after school since its my only day off this week from work. I also turn 21 on the 4th next sunday and it would be sick if I can get my turbo in before that..

patsmx5

iTrader: (16)

Ok I missed the thankyou. I was harsh. My point is you have to read to learn. I had many question too when I was first learning MS. I asked half the questions you're asking. From what I've learned, I can tell you getting in a hurry will get you nowhere fast. You need to take your time and understand what you're doing. It's like cheating on your HW in school. It might be easy and get you a good HW grade, but you'll fail all the test if you don't understand the material. Do your research and all will be right. Cut corners and you'll have little B.S. problems (grimlines) come back and haunt you. Seriously. I put +5V to my GMAIT and just about toasted it. Hence after reading AbeFM's post I messaged him to inform him he posted something that was incorrect, and he edited it.

Serper3

iTrader: (3)

So did abe say that? Or r u putting words in his mouth?
I am sry, I understand I can prolly do more research but I don't feel safe doing things to my car and risking things based on what others have said In the past in different situations especially with some of these wiring things since I am doing something which isn't done often. But yes like I have stated numerously, I am very greatful for everyones help.

Joe Perez

iTrader: (8)

There shall be an end to the bickering now.

Maharashii, if you didn't understand Abe's criticism, it was because you said "I'm not running vacuum to the MS." If this is true, it demonstrates that you really don't understand how all this works and need to think a little harder about how engine load is calculated. Don't take this too harshly- it's tough, and we were all clueless about this at one time.

Serper, yes, people sometimes put words in other people's mouths. I thought it was pretty funny, actually. For now, just chill. Also, you're right about the IAT sensor. One wire goes to pin 20 of the MS, the other goes to ground. Doesn't matter which is which. Lastly, my personal opinion is that the best points to take a MAP reading are the ports at the back of the manifold. The big hose that feeds the brake booster is fairly easy to tap into. And yes, you can share one tap with several devices. I have my MS, my dash gauge, and my WI MAP sensor all on the same takeoff, fed by a tiny little 1/16" hose. It doesn't take much.

Patsmx5, carry on,

Serper3

iTrader: (3)

Only because joe is a baller..
Jk

Serper3

iTrader: (3)

So the iat sensor has 2 wires coming out of it and one of them goes to the wire coming off my harness, one goes to ground and it doesn't matter which one goes where?! I love when things don't matter like that!

AbeFM

iTrader: (3)

Oooo - I feel pretty moderate. This whole thread is getting more moderate by the second. The edits are funny though.

That's why Joe's car doesn't make 1.8L power. Well, that and it's a 1.6.

Plus, with the broken foot, he can't really press on the gas.



You think that doesn't matter, try ignoring one of those polite notes from the IRS saying you ower them more money. :-)



Maharashii, not trying to insult you - and I've been guilty of it in the past - but try not to tell people things without qualifying how sure you are of your answer. It's good to give advice but I get a sense you still have a bit to learn. Stick with it. Nothing is worse than seeing someone copy something someone else wrote that was wrong, etc. :-)

Joe Perez

iTrader: (8)

Heh. Ok, number of complete, running engines currently installed in Joe's car: 1. Number of complete, running engines current installed in Abe's car: 0.

But yeah, I've been driving around in my grandmother's Toyota Solara for the past week. What a horrible, awful car. A/C ain't bad though...

AbeFM

iTrader: (3)

Maybe FL isn't filled with old people, maybe it just makes people old by making them rely on AC.

Left foot is bad, then?

Anyway, two points:
1) I have a large fraction of a complete motor. Probably .7 by volume, more by weight.

2) Both our motors are doing the same job, though I admit you could start yours up and listen to it rev.

______________
Anyway, I'm kinda excited to see this thread pick back up, I want to know if it's working or even close.

You knew, Serper, you can start the car (if the battery if good) without the alt part working. And you'll be more encouraged to go buy the wiring harness after your car runs. I drove mine around the block before getting it charging, TeamPlur too.