Same here, I've got at least one flakey coil now after running them in batch for quite a while off the stock ECU. I really wish we could get a dwell reducer that actually works. I think I have about 10 coils in the garage now, its going to suck when I finally get around to figuring out how to test them.

Also, the car idled way smoother on the cops than it did on the factory coilpack, even on the stock ECU.

How are you guys holding your coils down besides that piece of aluminum with holes in it. ???
I have an extra valve cover, thinking of partially drilling thru the material and JB welding bolts heads so the bolt shaft sticks up to hold the coils. :idea:

I just used a piece of copper ground wire with some fuel line slipped over it that had rings to the 3 valve cover bolts. Was effective, took luck to get the proper torque on the bolts to make the valve cover not leak.

This is what I had but never liked it. U have to scroll down a bit
DIY Stud of the Month -- DIY Tips and Tricks

Ok guys... I just completed a hack that gave me plug and play for my 95M. It isn't quite the elegant solution I originally envisioned, but it let me avoid tearing into the OEM coil harness.

Somewhere in this long 85 page thread, a lone voice asked one simple question that seemed to get overlooked in the heat of the ongoing discussion. I'd honor the name of the poster, if I could only find the post again, He certainly deserves full credit for the idea. The question (paraphrased) that he asked was, "Has anyone tried using a TPS to make COPS plug and Play?"

This idea stuck in my head because I too had noticed the shape of the connection was very similar to the coil connection. So when I picked up a used set of Toyota Matrix coils, along with a full ignition harness, I also grabbed a couple of Toyota TPS modules. These are the same as the ones used on 94 and 95 NA's, but Toyota used millions of them so they were cheaper.

Once the TPS is gutted, you have 4 perfect pins for soldering. The plug will not fit the Miata coil harness plug without a bit of modification, but the 4 external pins are a perfect match. It require removal of the plastic shielding surrounding the pins in order to accomplish a good connection. I'll have to use electrical tape to secure the mating, but it works quite well from all indications.

The car fired up first try and idled smoothly. It was too late for a test drive, but that will happen once I tidy things up and tie the coils down. Plug and Play is possible, even if the fix is less attractive than the hoped for direct connector match.

Steve

Steve, no pics?

I :fael: the connector off a dead NB coil pack. Its not super pretty, but should give a good connection. I've not assembled it yet so no pics heh.

I just bought the connector from eastern beaver. I of course removed the whole stock coil harness. So to add/remove my cop setup you had to undo the connector AND unbolt a ground terminal.

I was under the impression the coil side 4 pin connector was not actually available anywhere, or did you buy the TPS one? Got a link? It will probably be prettier than my sodoff coilpack connector mess

The coil side connector is easy IIRC. But I used the 6 pin connector that connects the entire coil harness to the car (because the coil harness is a sub harness). That 4 pin coil connector is a standard connector with a mate, but I cant confirm that because I cant open the google doc with all the connectors at work. To test, if the coil pack connector plugs into the CAS then there is no mating connector available.

for those who said my coils stick out like nobodies buisness

update with coil hold down bar

https://lh4.googleusercontent.com/-k...-no/2013-11-23

That's the way I mounted my coils with the bar across the top.
I should have gotten a patent :bowrofl:

dude its so simple and perfect!

Yeah but stupid me did not use a thick tubing like you did :vash:

hehe yea I wanted to make sure I wouldnt have any bending issues

How do you like the COPs so far ?

I'm back to stock since my MS1 decided to fry 3 of my coils

they are fine, seems more responsive (could be me wanted them to be lol)

I got the coils for free from a vq35, easy wiring just like toyota cops, plus it
makes me look modern :p

:)

I'm curious, why not use springs to hold down the coils?

I don't understand ...

where would the springs go ?

U mean the bar going across with springs between the bar and the coil ?

err my bad i should have been more clear. Little angle bracket on the valve cover bolts with springs that go up to the pipe instead of a hard mount.

Angle bracket like this but with the right diameter holes of course.

https://www.miataturbo.net/attachmen...ine=1385265438

Sorry it's late over here and some of my brain has leaked out of my ear so I'm not understanding you.

^^same here, but box wine may be the culprit...

Instead of metal brackets holding the bar down towards the coils use springs to pull the bar towards the coils to keep them down.

Whats the benefit? My coils arent being pressed down into the holes much at all, I measured the height so that the bar sits gently on top with the main goal of keeping them from popping out.

Benefit would be not needing to mess with the bolts every time you want to pull the coils, instead u just unhook the springs.

oh I dont need to mess the the bolts to undo the coils, I made the tolerance of the holes for the bar quite small so its tight and doesn't move, but I can pull it out if I have to.

Cleaner way to wire the coilpacks
 

I'm not sure if I'm the first person to do this or not, probably not. But I didn't notice anyone mention it, so I figured I'd share.

So there are two connectors on the front of the engine which feed the injector/coils/coolant temp. One connector is for the injectors and coolant temp, and the other connector has the coils wired in just by themselves. I chose to take my injector/coil harness apart, and remove the wiring for the coils, and use it to make a separate harness just for the coil packs. This was super easy to do, as the injector and coil wires are just taped together in a few spots, none of the wires are connected within that harness.

This gave a cleaner installed look, as it gets rid of all the wires hanging around at the back of the cylinder head. The new 'coilpack-only' harness gets routed forward instead of rearward, and plugs into the vehicle harness at the normal location.

I have not done this, but it is my plan to do that, or at least take the wires out of the main harness even before they come forward (split the harness where the EGR leads come out). I don't understand why the coil harness comes through the firewall, to the front of the engine, then back through the intake manifold to the coils. As I plan to repurpose the EGR wires to drive coils 3 & 4, I may even add a connector or connectors at the rear and stil bring the harness forward. Third choice is to bring 1 & 2 from the front (like you did) but bring 3 & 4 from the back; running sequential.

Agreed, doesn't make sense why they come all the way forward, then back again. I was thinking about trimming the vehicle harness back, so the coil wires come out of the vehicle harness at the back of the engine as you mentioned. But, I ran out of motivation to modify the vehicle harness!

Repurposing the EGR wires to run sequential is brilliant. Already in the harness so it'd be a nice clean install.

I suppose the cleanest way to do it would be to integrate the COP wires/connectors into the vehicle harness, so there was only one wire loom running across the top of the engine.

Welcome to the miata harness. It was either designed by 5 engineer's that hated each other's guts or one guy who was bipolar and beyond incompetent.

Alright, so 85 pages later and my brain is moosh.

As I understand it, on my 94, the ignitor is built into the coilpacks.

Because the Toyota COPs have the ignitor baked right in, I can toss my OEM coilpacks, cut the coilpack connectors, and wire directly into the harness (using 12ga and 16ga, where appropriate). Yes?

Or you can be smart and buy the 6 pin connector (its like $7) that is on the soil pack sub harness and make something that isnt hacked together.

Is that 6 pin or 4 pin on a 94?

6, one of the pins is blanked out though, so it only uses 5. The 1 extra wire is the tach signal.

Ahh, tach. I've been staring at my NB harness too much recently.

Abe is on the money.
Just measured wires on the plug, and Toyota uses 16AWG for ground, 18AWG for everything else (tach, trigger, 12V)

was anyone contesting his 6 year old post?

is there a dxf anywhere for the bracket?

i have a laser cutter but need exact dimensions

Can't find one or dimensions that i can copy

https://www.miataturbo.net/attachmen...ine=1411007128

Want to make sure im correct

You don't have a valve cover?

I'm pretty sure it'll have the dimensions you need...

If there was a dxf readily available it would have made life easier. No need to be a smart arse

I found what i need on grab cad

https://grabcad.com/library/mazda-b6-coil-adapter

Necro-quote, but was this misfire without rhyme or reason?

I'm running in batch, but there's a big resistor thing in the harness. Been fighting a completely random misfire.

It had rhyme and reason, but solving it was suck. It only really did it when hot, so I'd have to drive it until things got hot and then sit on the side of the road swapping with a spare until it went away. Easy peasy.

What's the resistor for? I don't remember seeing that in any of the writeups.

Would it be ok to solder the 1Kohm resistor inside the igniter box between the blue and yellow/blue from one spade to the other? That would keep the resistor from becoming damaged and/or breaking.

Also, I got a set of resistors at Radio Shack, they say "1k ohm, 1/4watt carbon film resistor", is this the right one?

And, do I really need to add the 10000uf capacitor to the 12v and ground?

Thanks!

The oem pull up is in that white black wire. Have you built your ms yet? It'd be preferable to add it in that harness.

Cap is not needed

Would this work for less clutter? (Bad picture, but I would solder a resistor inside the igniter connecting Blue to Blue/yellow and then jump Blue yellow to black/white)

I have MSPNP1

What I dont understand is why that schematic shows the resistor bridging blue and yellow/blue, why not just place the resistor between the yellow/blue and white black instead?

Here is a better pic

Because the resistor is to provide a pull-up voltage for the ECU to read. The yellow/blue, and white/black should be connected together to connect the tach signal from the coils to the ECU wire.

I gutted the igniter, made a harness and soldered everything today, including the resistor. Not very pretty but it works! I used 12g wire for the 12v and ground signal and 18g wire for the rest.

Set my cranking dwell to 3.5ms and running dwell at 2.5ms and the car runs well. Thanks for all the help

https://www.miataturbo.net/attachmen...ine=1417997087

Mix up some epoxy or use electronics grade RTV and pot this lest the vibration break the resistor leads.

I was thinking about filling the entire thing with jb weld. Would it work?

Hot glue. Tape closed. Bolt back up. Forget.

Yeah, hot glue will work also, and is readily available. I would guess JB Weld is conductive.

I'll get clear loctite epoxy. I don't have a hot glue gun. Jb weld has iron I believe

Inter web search shows JB Weld iron particles to be small enough that that bulk material is non-conductive. Still, I would prefer another, unfilled material. If you had stress sensitive components, then a more flexible urethane would be the normal potting choice, but epoxies are used, as well as electronic RTV, and, as Scott pointed out, hot melts.

I just didn't want you to do nothing, but it sounds like you had planned to pot.

For the 1.6 ignitor, the circuit board is not reconnected?

Sorry if this is already in this thread but I've scanned over the 80+ pages of it and didn't see any mention relating.

Toyota COPs installed. Called DIY and they confirmed that my Megasquirt 1 has the capacitor built in. I did not install the resistor though but my tach works fine, sort-of.
Engine idles and cruises better than with OEM coils.
Problem is when it gets into boost above 6psi the engine shuts down and tach drops to null for a split second, like I turned the key off and back on real quick. Damn neck snapper. I can't get Tuner Studio to link up so no diag via software (whole other issue I'm working on).

Is this something that the resistor would help or yall have any other suggestions?
Thanks for any help fellas.

Are you running sequential ignition?
If so, revert back to wasted spark, your problems will go away.

Also, check charging voltage when the condition you describe happens. Does the voltage spike?

You might wanna log this event to verify.

Not running sequential. Check charging voltage? Can't log anything. No PC connect right now due to other issue.

I had the same thing happen when I first went out with my turbo. Logs showed it to be the overboost protection kicking in. My turbo is only set for 7.5psi and I had overboost setting at 150kPa with 10kPa hysteresis so it would hit peak boost then stop spark for 1/2 second while MAP dropped to 140kpa then back on til peak boost then stop for 1/2 second again etc.

Worth checking. I since set my overboost to 170kPa with a 1kPa hysteresis so I can turn up the boost to 10psi gradually.

Cheers
Stot