Miata Coil on Plug DIY - Full HowTo!

[@OGPedXing]

Note: Toyota COPs have a lower dwell time than stock. If you have an aftermarket ECU then you can change it as I show in the video. If running the stock ECU you may need to find a way to reduce the dwell or else it will shorten the life of the coil. Check out this how-to for a circuit: forum.miata.net/vb/showthread.php?t=277963

[@mrmohr2]

I am running MS2PNP

[@leesmith1511]

OGPedXing wish you were here

[@theo_korner]

Not doing this will shorten the life of the coil how much? Im using this as an emergemcy fix. Will it work for about 200km?

[@OGPedXing]

@@theo_korner it's hard to tell, it's all about heat. These coils can take some abuse but if they're old (I got used oem when I did mine) then they may not make it. But I've talked to guys that lasted 6 months or more on them with the stock ECU.

[@theo_korner]

@@OGPedXing thanks, that will do

[@RalstigRacing]

Thanks for the OEM harness connector. I've made a few of these over the years and ended up making my own connector. I love a true PNP solution.

[@OGPedXing]

All credit to Ballenger Motorsports...they carry a ton of Sumitomo connectors which is what Mazda likes to use and I like to check back there periodically to see if they add anything. I've searched Sumitomo parts catalogs before and could never find the coil side of this connector pair. Many people have hacked an old broken coil pack to make their own connector but that's time consuming. I was super happy to find these.

[@RalstigRacing]

@@OGPedXing That's what I did before, was a real pain. I even gutted an old igniter for a 92. I hate messing with factory wiring and will almost anything to prevent that.

[@marceloxlago]

I am studying to do this (one coil per cylinder) using the original MOTRONIC 1.5.4 injection on an ECOTEC (OPEL) engine. Currently coil and cables are used. In the coil arrives three wires, the positive and negative of the primary coil for cylinder 1.e 4 and negative for the primary coil for cylinder 2 and 3. The wires come straight from the motronic module 1.5.4.

[@coldmutton]

Thanks for posting this up. I hate cutting the main harness on anything and have been looking for the plugs to plug into my 94's harness.

[@OGPedXing]

I feel the same way. Added bonus: You can solder everything up inside in comfort rather than leaning over an engine bay. Plus the whole thing just unplugs and can be removed if you need space to do something behind the head.

[@lazzer408]

Hell yeah. My COP mod is still alive and kicking! \:D/

[@OGPedXing]

Awesome 👍!

[@mrmohr2]

Thanks for such a well done video! You're not quite as animated as Greg but your information is quite good!

[@OGPedXing]

Thanks, I love Greg's stuff as well.

[@adamfalzon4745]

Awesome job securing the plugs I’ll definitely be doing that. I would have soldered the joins. Would love to know how to get the rev tachometer working again

[@OGPedXing]

There are a couple of tricks to get the tach working if it's not getting it from the ECU...what year and ECU are you running? I did the soldering off screen, but yeah I like how clean the harness comes out with solder connections vs crimps.

[@tonyyo1312]

Nice thanks for the informative video on the diy. Just ordered my coils!!

[@robertcollymore4330]

Very detailed and informative video,keep up the great work.

[@harrisdoesthings]

Awesome vid dude! I can't wait to document mine (: cheers for doing it first!

[@kevinsaeed9817]

I decided to attempt installation. I watched the wiring section a few times and got that "baller" harness plugs into coil pack connector for 1&4. Baller harness 12v lead goes to cop 1 and cop 4 power (same for GND, Trigger, Tach). Then repeat this for the second baller harness but connect leads to cop 2&3. Is this an accurate summary? Love the baller/street cred tributes to Greg. Lol. Keep these videos coming!

[@OGPedXing]

Haha, thanks. Yep, that sounds right!

[@kevinsaeed9817]

@@OGPedXing one thing that confused me a bit was the additional GND wiring while testing. Is it not enough that the COPS are plugged into the connector which has wiring for GND?

[@OGPedXing]

I may have to rewatch the video, lol. Basically the grounds are tied together further in the oem harness anyway. If you use the oem coil pack plugs, there are two ground wires but these both go to the same place. Same with all the 12v power wires and actually tach as well. Only the trigger is truly split between 1 and 4 vs 2 and 3. So as long as each cop gets power, ground, and tach it can actually pull from wherever.

[@kevinsaeed9817]

@@OGPedXing for the test, you had some leads around what looked like the spark plug threads running to what looked like a jumped cable with the other end of the jumper cable clamped on the engine hook. Was wondering why this was needed even though the cops were plugged into 12v/GND. Maybe cause the plugs weren't screwed into the head? I want to try the test but being a novice looks a bit intimidating lol

[@OGPedXing]

@@kevinsaeed9817 oh! Right, yes it's very important for the plugs to be grounded themselves. They normally ground through the head, correct. So when outside the head you need to give it a ground path via the threads otherwise damage could result to either the plugs or the coils. Some people just set them on the metal valve cover but mine is painted so I like my wire set up.

[@mrmohr2]

I have turbo charged my 1990 1.6 and one of the coils is not strong enough for the turbo. This method is substantially less expensive than Greg Peter's LS1 coils, and $100 spark plug wires.

[@mannys18s]

Great info, awesome video. Might try cop soon.

[@kaloyankrastev638]

Thank you for the great guide! What is still not clear to me is, the stock miata trigger voltage is 12v as far as I know, while the Toyota cops take 5v trigger signal normally. Is this a problem, or are they good to use like that?

[@OGPedXing]

Yes, I believe the Toyota cops need a minimum of 5v but actually work fine with anything between 5 and 12. I think the stock ones also do this but that the spec is looser on the Mazda coils and it's more stable at 7 to 12. But either way, the Toyota cops are happy at 12, no problems there.

[@kaloyankrastev638]

@@OGPedXing thanks for the clarification, your imput is very helpfull!

[@shawnolinda2972]

Are the spade plugs the same on a 1.6 harness rather than a 1.8 harness?

[@matthogue7600]

was super excited to do this as my wiring for my miata 1.8 is old and the coil packs are expensive, switching to this would make my motor run again and save me cash. was super happy until the megasqurt part came up. i knew this was too good to be true with a stock ecu. -_-

[@OGPedXing]

Yeah unfortunately the long dwell time from the stock ECU tends to over heat the Toyota coils, shortening life. I've heard some people run them for quite a while with no problems on the stock ECU, but maybe they live in a cold climate.

[@jerryharrison7026]

Great video. Which AFR and Boost gauges were those.

[@OGPedXing]

The are from speedhut.com. They do all kinds of gauges which you can customize. I set up mine to be analog with specific fonts and tick marks to match other things in the car.

[@matnoor6743]

Where the place of transistor power is... Or how is the fizikley

[@moneeb343]

Are these considered "wasted spark" ? Can you explain that a bit? I can't find much information online

[@OGPedXing]

They can be set up however needed, wasted spark, fully sequential, etc. Wasted spark just means that it fires both the actual cylinder that's receiving fuel in the combustion sequence as well as it's paired cylinder. For a 4 cyl car, is 1 and 4 and then 2 and 3. This does not reduce the spark power applies to the combustion cylinder because the other wasted spark is under very little pressure and sparks easily with almost no amperage draw. So all the energy is happening on the combustion cylinder.

[@moneeb343]

@@OGPedXing I guess I am wondering if I SHOULD make it sequential spark or keep it wasted? Pros and Cons?

[@OGPedXing]

I'd keep it wasted spark for any car that doesn't have the wiring stock for sequential. Sequential spark is a tiny bit more efficient than wasted but unless the coils are very under powered, it will make no performance difference.

[@moneeb343]

Would you mind adding a link to those two plugs above the 4 coils at around 0:30 please?

[@OGPedXing]

That was the bit.ly link in the description, but here it is in full: www.bmotorsports.com/shop/product_info.php/products_id/4161

[@luisperez0583]

Hi greetings brother I have a 4g63 with a sem 102 ms3 program. I wanted to know how I can do the test for my coils since when I do that test I don't It allows. I have aem 30-2853 smart coil

[@OGPedXing]

The other thing you can do for testing if the screen isn't there in tunerstudio is pull the fuel pump fuse and then crank it. This is more intense on the battery so you'll want to connect it to a charger or jump pack to avoid running the battery down if you are cranking for a while.

[@luisperez0583]

@@OGPedXing thankd man

[@christophermartin4091]

Excellent How-To. Thanks!

[@connormckenzie9266]

Great vid im going to be attempting this soon

[@almuz73]

On 14:09 , there are two sockets fron the coils, how do you connect this to the single oem socket ?

[@OGPedXing]

If you have an earlier Miata, 90 thru 93 then you'll have a single plug for the ignitor vs 94 and up have two plugs for the 2 coil packs. The wiring in general is similar but I haven't seen a female plug for that sold that will go into your oem harness directly, unfortunately. What most do is cut off the plug from the oem side and wire it to your new cops harness directly. There are some decent diagrams here wiki.fome.tech/Vehicle-Specific/Mazda-MX5-Miata/Miata-COP-Conversion/

[@Samakaabtv]

My vitz asz1 toyoyoto is not starting. Battery is good and fuse is good sparkblug is good and fuel bumb is good so what you can helpme sir

[@OGPedXing]

If it's cranking and you have spark and fuel then check that the timing is ok.

[@Brizzle_718]

so in the tuneing side do i not set the car to coil on plug in the spark mode

[@OGPedXing]

If you have wiring for sequential ignition then you can use the cop setting, otherwise it will work like wasted spark. (Sometimes known as wasted cop). In an na miata for example, it will be wasted spark. There's really no downside to this, the non firing cylinder won't pull any amps, all of it will go to the firing cylinder even though two plugs are technically firing at once.

[@Brizzle_718]

@@OGPedXing thank you for the quick reply yes I’m just getting a wasted spark pnp setup so I will just run wasted spark

[@allyh6557]

Great video. Do you know if the process is the same for the NB?

[@OGPedXing]

Yes pretty much. The later NA s (96+) and NBs have a three pin connector to the coil packs. The Toyota cops have 4 pins... you're going to ignore the tach pin - leave it unconnected. The tach is driven from the ECU for the later cars. So all you need to wire up is the power, ground, and trigger for each. The there is one trigger wire for cylinder 1&4 and another for 2&3.

[@allyh6557]

@@OGPedXing thank you for clearing that up. Much appreciated.

[@tonyhamre61]

I am still a bit confused on what to do with the ignitor for the 1.6l stock ECU. I can't find any wiring diagrams that are still viewable so I am not sure what to do with it.

[@OGPedXing]

I think most just cut it at the connector and wire directly from there. It's simplier although your cop harness is now part of the overall loom and can't be unplugged separately. Here's a forum thread with the pics: www.miataturbo.net/useful-saved-posts-8/upgrading-coil-plugs-all-years-cop-writeup-12704/

[@edwardharvey5839]

The wires attached to the coil, are they the distributor wires?

[@OGPedXing]

Each coil has a power, ground, trigger, and tach signal wire. When set up with coil on plug you no longer need an ignitor such as on 90-93 years Miatas or a shared coil pack as on 94 and above. If you have an actual mechanical distributer on your car (not a Miata), you won't be able to do a direct conversion to coil on plug.

[@angelvazquez5372]

Can you run sequential ignition like this or would i have to tap into wires from my cas??

[@OGPedXing]

For a 94 and above (and the California version of the 93) it is wired already for sequential so this will work no problem. For 90-93 check this out...scroll to near the bottom on how to wire it with a megasquirt: www.megasquirtpnp.com/docs/mspnp_g2_mm9093.php?isModel=1

[@DirtBikeRodz]

Do i need to change my spark plugs? The toyota coils don’t lock in so the spring just have to be in contact with the spark plug? And bolt it down so it doesn’t move? Or something is wrong on my end? 1999 mazda miata

[@OGPedXing]

That's correct, they don't lock down like the normal plug boots, the bolt on each coil holds the tension on it.

[@DirtBikeRodz]

OGPedXing thank you so very much.. love the content, you help a ton with my build🙏🏽🙌🏽

[@f0deraro]

Curious what you're running for Spark Plug gap and if you've made any changes after tuning. Thanks!

[@OGPedXing]

I'm gapped at 0.040, once I went turbo. That's been very stable although this setup is only doing about 14 psi. Without the cops it would need to smaller.

[@f0deraro]

@@OGPedXing I also did the COP setup, so I'll start with 0.040, thank you!

[@f0deraro]

@@OGPedXing 14 PSI on the T25? What kind of power are you making?

[@OGPedXing]

@@f0deraro I haven't dyno'd this exact setup but around 240 HP peak or around there. This turbo gets tapped out pretty early but I love the instant spool and midrange torque.

[@beazleybub5085]

How do you keep debris or water from going around that plate and down into the plug wells?

[@OGPedXing]

It's a pretty sheltered area so I've never had problems. For dust I think it would be no problem...the plate fits tightly against each plug hole and the top is covered by the rubber cop boot. For water I've never seen that area wet...check your cowl weather strip if you see water there. I guess you could use a little rtv or some gasket maker around each hole but I'd say that's overkill.

[@jaredscott1349]

@@OGPedXing just an idea but you could also cut a piece of flat rubber the same length of the aluminum bracket including holes and pinch it under it. I/E an old bike tube

[@OGPedXing]

Good idea!

[@ianrasch]

Are the settings the same for a 1.6? I have seen people take the duration down to 0.7ms; what do you make of that?

[@OGPedXing]

It's not going to do too much. This is the time the MS will wait before starting to charge again and is used to ensure the burn has happened before starting to charge again (like at high rpms). Since the Toyota COPs charge pretty quickly, this is not really a concern. A normal value is about 1 ms. Dwell on the other hand needs to be set correctly based on the coil and the voltage. Nominal is 2.5 ms at 12v. So your dwell correction chart should be compared to your actual dwell times from logs and corrected as needed. Normally you'll be at 13.8 to 14.4 volt when driving. So the actual dwell needs to be 2.5 ms at your normal voltage. Edit: oh also the settings will be the same on a 1.6.

[@NostalgiaHeroDriving]

Did you have any trouble getting a tach signal with the megasquirt? Or did it function like stock?

[@OGPedXing]

Mine worked fine but it can depend on how your MS is wired, the generation of Ms, and also the year of the car. I think 94, early 95 and older require the tach signal from the coil to be routed back to the ECU. With my 94 I tied all the tach wires from the coil packs together and connected them to the original tach wire in the loom. In some cases you can put a small resistor (1k) in the diag box between ig- and b+ to provide a pullup for the gauge.

[@dt205]

"For '94+ Miatas, PNP connector to car's harness." is this different on pre 94 miata's?

[@OGPedXing]

90-93 Miata's have a different harness due to using an ignitor in addition to the coils. There's a single connector going to the coil pack but you'll actually want to connect before the ignitors. Many will take apart the ignitor plug and tap in there for a clean look. The part I referenced for 94+ is the male coil connector plug and works for 3 or 4 pin coils on 94-05.

[@kevinsaeed9817]

Is it possible to plug the connector with the brown/yellow wire into either of the coils or is it dummy proof and only plug into the coil pack on the passenger side (where 4 and 1 connect to in 4123 order)? I didn't take a picture and trying to get it back together. Currently brown/yellow is on the driver side coil and brown is on the passenger side coil. I think I have them on backwards (for plug wires in 4123 order) but wasn't able to get the connector w the brown/yellow wire into the plug on the passenger side coil no matter how hard i pressed?

[@OGPedXing]

You'll need the brown yellow to go to whichever coils are on 1 and 4 and the solid brown to go to 2 and 3. On the stock coil packs you could swap them but only if you also swapped the plug wires as well. For the cops it's usually harder to move them around between cylinders.

[@kevinsaeed9817]

@@OGPedXing thank you for your content. Going COP is what got me to this video. Until then, since my brown/yellow will only go into the driver side coil for some reason, can I just switch the plug wires so its 2341? BTW, this is me trying to put things back together after going through your coolant reroute video. I Should have marked the plugs :(

[@OGPedXing]

@@kevinsaeed9817 yes should be fine if I'm understanding correctly. Just swap the 1 and 4 wire over to the driver side pack and 2 and 3 over to the passenger side. Within one pack also it doesn't matter since they both fire at once.

[@kevinsaeed9817]

@@OGPedXing I would like to try and start it how I have it knowing its wrong and then switching over the wires and try again to see what happens. Is there any harm in doing this, im thinking the car just won't start when trigger signal for cyl 1 is going to 2 & 3? Thanks for your help, I shoukd be able to fill her up w coolant and get her started today.

[@OGPedXing]

The only small risk is extra unburnt fuel in the cylinder. Just don't crank for too long. You can also put the car into flood clear mode by flooring the accelerator while you crank. But it takes a lot of fuel to hydro lock something, not much of a worry.

[@mrmohr2]

Do you think these Toyota cop plugs would be strong enough for a 250 horsepower 1.6. currently I'm estimating I'm running 5 - 6 lb of boost and maybe 150 horsepower. The stock coils worked well for the first two days. I don't really want to go the whole $500 route that Greg did on his Miata if this method will work.

[@OGPedXing]

@Mike Mohr Yes, the Toyota COPs should work well. You won't be able to gap them as large as the LS coils but they'll be ok up to around 15 psi. The price is hard to beat! Keep in mind the dwell issue though, these are most reliable when combined with an ECU that allows you to set coil dwell time to about 3.5ms crank and 2.5ms normal. (Less than stock).

[@themindpower94]

Hi, may I know how can I make this on car that have only 1 ignition signal from ecu.

[@OGPedXing]

What car do you have? A four cylinder should have at least 2 for wasted spark - one trigger for cyl 1 and 4 and another for cyl 2 and 3.

[@themindpower94]

Daihatsu charade gtti. 3 cylinders.

[@OGPedXing]

@@themindpower94 interesting. I'm not familiar with it but it may be a two cylinder wasted spark meaning that the ignition is triggered every cycle for all cylinders but fuel is present in only one at a time. In that case you tie all the coil trigger wires into your single trigger wire from the ECU. You'll want to try to find out if your engine and ignition does indeed work like that, but it seems likely.

[@themindpower94]

Okay i will give it a try.

[@matnoor6743]

Wiche wire for... Ignition coil bos

[@shawnlively4702]

Did you ever get the Measurements / Dimensions of your Center Plate?

[@8145dwerdna]

Did you manage to write the dimensions for making the plate? I wouldn't mind having one lazer cut at my work out of stainless.

[@OGPedXing]

No, afraid not. Thanks for the reminder though, next time I have it out for plug changes I'll try to measure it precisely.

[@steelwitness]

is this not really just a better option for anyone with old coil packs? if your coil pack goes out just do this because its the same price as a new oem mazda coil pack. and if they go out again its cheaper to replace coil on plugs.

[@OGPedXing]

Agreed!

[@davemitchell7732]

Hi, thanks for the vid. Is this a 1.6 or 1.8? Thanks

[@OGPedXing]

Mine is a 1.8 -- for the 1.6 the process is basically the same except the wiring comes from the plug to the igniter which the 1.8s don't have. But basically the power wires are shared, ground is shared, you need to get the trigger wires for each cylinder (1 and 4 then 2 and 3) set up. And also I think tach is still used.

[@90lxfox3]

would this work on a stock ecu

[@OGPedXing]

The problem with stock is with the dwell time...it will cause the cop to charge for a long time causing more heat and a shorter life for the cop. Some people seems to be able to get away with it for a while but I don't really recommend it. Basically the other options are to find a different cop with a longer dwell, use an aftermarket cpu (megasquirt, speeduino, rusefi, me221, etc) or build an add-on circuit to reduce the dwell from the stock ECU.

[@steveaguero8483]

Do you need ms or a standalone to run them this way?

[@OGPedXing]

The short answer is yes, a standalone is the best way to handle it. The other option is to find something that can reduce the dwell time of the stock ECU or find a different coil with a similar dwell as the stock packs. I think there is a particular motorcycle coil that some people have used with success. The rest of the wiring will be the same as shown in the video except with a different connector.

[@HyperspeedMedia]

great info

[@shaneclk9854]

What is the tach for

[@OGPedXing]

Depending on your year of car, it provides the rpm output. Some cars give this from the main ECU, but some need it from the coils.

[@drivertech3994]

Hello nice job mate congrats , can you tell me is there a the differences before after on dyno or anything . Thank you i subscribe and like .

[@OGPedXing]

If you're naturally aspirated then no, it's a bit stronger but it won't add power. If you have a turbo then it will help. You can gap your plugs larger (like .040inch or 1 mm) which will allow for better ignition under boost pressures. You can run the Toyota cops to about 20psi. The stock ignition starts to blown out at maybe 12 psi and you have to gap it very small, like down to .020 inch or .5 mm.

[@drivertech3994]

OGPedXing thanks a lot for information

[@davidlyall4769]

Im doing a video of were to get it at the junkyard. Trying to show it can be cheaper then people think. An to promote recycle

[@OGPedXing]

Good deal! Yeah these coils came on a large variety of Toyota and Lexus vehicles. If you have a good yard near you they are easy to pull and then the rest is just some minor Fab work and soldering.

[@MrSprintcat]

Looks nice to bad you can't use the stock ecu.🤣

[@dannyphan543]

Sick