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Official LH2.4 EZK Wasted Spark Conversion - Installation Instructions

Check your wiring. Also try running off the stock ignition side if you haven't removed those components yet to make sure your ezk didn't get goofed during the soldering.
 
I don't have one of those unfortunately.
Tried multiple coils and amplifier.
Getting 12v at injectors, coil, power stage
Power stage gets constant ground, not 12v. It takes the pulsed voltage from the EZK and switches on/off the ground signal to the coils. The coils get 12v constant with key on.
 
I wired up the new board a while back and it's all working flawlessly. However, I can't get the tacho to work, I've tried using the provided diagram but no luck. So to clarify...

Original EZK signal wire to ignition module has a 1k resistor added, which then connects to the middle leg of the transistor. One leg goes to ground, the other to a Y - one to the relay, the other to the tacho. Finally connect the switched 12v to the other side of the relay.

Is that correct? Everything else working great, just can't get the tach going.
 
I wired up the new board a while back and it's all working flawlessly. However, I can't get the tacho to work, I've tried using the provided diagram but no luck. So to clarify...

Original EZK signal wire to ignition module has a 1k resistor added, which then connects to the middle leg of the transistor. One leg goes to ground, the other to a Y - one to the relay, the other to the tacho. Finally connect the switched 12v to the other side of the relay.

Is that correct? Everything else working great, just can't get the tach going.
That's way more complicated than it needs to be. I just took the original ignition coil out and replaced it with a relay (with the contact removed so it's quiet). Then I had a working tach. Then, completely separately, I put a 960 ignition module by the coil on my valvecover with inputs coming from the ezk board. This now unrelated system gave me working dual-channel ignition.
 
That's way more complicated than it needs to be. I just took the original ignition coil out and replaced it with a relay (with the contact removed so it's quiet). Then I had a working tach. Then, completely separately, I put a 960 ignition module by the coil on my valvecover with inputs coming from the ezk board. This now unrelated system gave me working dual-channel ignition.

The main reason I didn't do it this way is that I removed the original ignition module as I used the heatsink for the new 960 module. I was following the diagram on the first page of this post
 
The main reason I didn't do it this way is that I removed the original ignition module as I used the heatsink for the new 960 module. I was following the diagram on the first page of this post
https://smile.amazon.com/gp/product/B0012P2EQU was pretty easy to modify to fit the 960 module. If you're set on getting rid of that 'extra' module, let's check some basics since your description of your setup sounds good (although I can't personally verify what resistor ohms are appropriate). What transistor did you get? Any chance it's PNP and not NPN? Or, maybe you have the collector and emitter wires backwards?
 
Alright guys...so I've been running my wasted spark setup for just shy of a year now; and now I've run into some issues

Link to my nonperformance thread...
https://forums.tbforums.com/showthread.php?t=349030

90 740 lh2.4
Miata J702t igniter
Bosch 2x2 coil pack
Buchka WS board
214? Gold box chipped ezk

In the onset of boost during a wot pull otw home last week, the car stumbles heavily, pops, farts and all the sorts. Limp it home and after some troibleshooting I've come to the conclusion I have no spark on cylinders 1 and 4.

Swapped coilpack with spare, nada
Swapped working igniter from my brother's same setup, no dice.

Break out the meter....

To the coilpack, middle power wire gets 11v key on, 9.5v while cranking.
Both outputs going to the coil pack for each bank of coils (OC1 and OC2) both show 0v while cranking. Not really knowing what I'm doing, I thought that was odd. Considering cylinders 2 and 3 have enough spark to run the engine.

To the igniter...coming from the ezk (pins IB1 and IB2) they both gradually increase in voltage while cranking. From 0v to 1.5v within 4 or 5 cranks.

Igniter has good ground

Grabbed the ezk out and inspected the connector I used to go thru the box and all looks good. Everything is still solid and not touching. Haven't opened the ezk yet but I hot glued everything in there so I highly doubt anything funny happened in there...

Any suggestions? Any wisdom anyone can share on how to diagnose further rather than rewiring everything?
 
Alright guys...so I've been running my wasted spark setup for just shy of a year now; and now I've run into some issues

Link to my nonperformance thread...
https://forums.tbforums.com/showthread.php?t=349030

90 740 lh2.4
Miata J702t igniter
Bosch 2x2 coil pack
Buchka WS board
214? Gold box chipped ezk

In the onset of boost during a wot pull otw home last week, the car stumbles heavily, pops, farts and all the sorts. Limp it home and after some troibleshooting I've come to the conclusion I have no spark on cylinders 1 and 4.

Swapped coilpack with spare, nada
Swapped working igniter from my brother's same setup, no dice.

Break out the meter....

To the coilpack, middle power wire gets 11v key on, 9.5v while cranking.
Both outputs going to the coil pack for each bank of coils (OC1 and OC2) both show 0v while cranking. Not really knowing what I'm doing, I thought that was odd. Considering cylinders 2 and 3 have enough spark to run the engine.

To the igniter...coming from the ezk (pins IB1 and IB2) they both gradually increase in voltage while cranking. From 0v to 1.5v within 4 or 5 cranks.

Igniter has good ground

Grabbed the ezk out and inspected the connector I used to go thru the box and all looks good. Everything is still solid and not touching. Haven't opened the ezk yet but I hot glued everything in there so I highly doubt anything funny happened in there...

Any suggestions? Any wisdom anyone can share on how to diagnose further rather than rewiring everything?
Ignition coils get ground pulses from the igniter so unless you're measuring from those pins to battery positive, your 0v reading makes sense.

It sounds like you're using a multimeter which is kind of limiting since it doesn't graph like a good oscilloscope (pretty cheap online and well worth it for diagnostic use so you can save your waveforms and share to help with diag).

Check your trigger wires going into your ignition coil. Hook the neg lead to one of the coil triggers at a time and the pos lead to battery +. Watch while cranking (should unplug injectors so you don't wash the cylinders with gas). Should see 12v pulsing on each trigger.

Your issue sounds a lot like what happened to me when I got water ingress within the igniter connector (which degraded performance and caused one set of cylinders to intermittently lose spark).
 
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Your issue sounds a lot like what happened to me when I got water ingress within the igniter connector (which degraded performance and caused one set of cylinders to intermittently lose spark).

This is interesting. I don't think you've mentioned that shortly before this your heater core failed. I know you checked igniter but maybe moisture affected your ezk/wasted spark board. We should have thought of this already but just grab my ezk and plug it in. Mine is very accessible right now.
 
I'm glad I know I can check for the 12v pulses in the coil harness. And yeah never really thought about the heater core causing problems. I'm wondering if I can open up the igniter pigtail and check out the contacts. Lol and yeah accessible being laying in the back seat area...

I should really invest in an oscilliscope sometime soon. Learning to use it sounds fun and rewarding
 
Ordered a new connector last Thursday from a miata forum so it should be here either today or tomorrow.

But until then I took the meter and tried to measure the pins coming from the igniter going to the coil using the method described above.

So I've had to look back thru pictures and diagrams, and then had to remember the outputs of the WS board are switched.

On the bank of coils that are working I'm getting a seemingly constant 11v with key on and while cranking. The other bank (the one side that doesn't have spark) ha's 0.3v with key on and increases to about 1.5volts while cranking.

Sound about right? At least both sides aren't the same so I know something is wrong there
 
Before I wire this connector in and try it out I undid the harness and found this...it was probaby like this on the first one but I just didn't care to ask.

The two outputs that go to the coil are wrapped together separately and wrapped with bare wire not connected to anything...important to replicate this the whole way to the coil or no? Cause I didn't the first time...

<a href='http://i.imgur.com/mufjjqy' title=''><img src='http://i.imgur.com/mufjjqyl.jpg' alt='' title='Hosted by imgur.com' /></a>
 
Before I wire this connector in and try it out I undid the harness and found this...it was probaby like this on the first one but I just didn't care to ask.
The two outputs that go to the coil are wrapped together separately and wrapped with bare wire not connected to anything...important to replicate this the whole way to the coil or no? Cause I didn't the first time...
I didn't twist the wires like that but I'm not using a Miata coil so YMMV. Typically twisted pair wiring like that is a good idea when you have two wires with alternating pulses bundled together although I haven't seen them with shielding like that. Try disconnecting the wires at the EZK module and see if you get pulsing voltage coming out the module. I don't know if your meter will pick up the short ignition pulses, check out the uScope. It is only 1 channel so you can't compare the two ignition channels at the same time but it's only $150. You could also just use LEDs connected from ground to each channel and see if they alternate blinking.
 
Leds are a good idea. That was my thought, that the pulses are to short for themultimeter to pick up so it just reads 12v constantly. I wired in the new connector and it seems I have 12v on both outputs all the way till the connector at the coil. 12v right before the connector, but if you check the pins it shows 0v.

So either I fudged up the reading before or both connectors had bad pins in them. Most likely I messed it up. But this time I'm positive there is 12v going to the coil on both outputs but somehow loses all voltage thru the 1-4 pin. I'm gonna try and grab some crimp connectors and do away with the land Rover connector for testing purposes
 
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It's running on all 4!! Crimped on some relay connector butts that I had and pushed them onto the coil pack. Fired instantly and runs smooth! I didn't let it run long because I now need to go back thru and resolder everything I cut and twisted together.....

But it's running!! I'm estatic right now!
 
It's running on all 4!! Crimped on some relay connector butts that I had and pushed them onto the coil pack. Fired instantly and runs smooth! I didn't let it run long because I now need to go back thru and resolder everything I cut and twisted together.....
But it's running!! I'm estatic right now!
So the issue was a poor connection at one or more of the terminals at the coil?
 
Yes. Apparently the pin for 1-4 in the female connector going to the coil is corroded or something. I cut it off and used butt connectors to connect it directly to the coilpack pins.

I mean, I wanna say I didn't buy another igniter connector for nothing...but at least this one has a longer pigtail coming from it...
So now I'll buy a new bosh 3 pin connector off ebay and should be good to go.
 
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Yes. Apparently the pin for 1-4 in the female connector going to the coil is corroded or something. I cut it off and used butt connectors to connect it directly to the coilpack pins.

I mean, I wanna say I didn't buy another igniter connector for nothing...but at least this one has a longer pigtail coming from it...
So now I'll buy a new bosh 3 pin connector off ebay and should be good to go.
Careful with the ebay connectors, they're often not the sealed type. I bought a pack of them which came with wire seals but the holes were square so the round seals didn't actually work. The Bosch OE part number is 1237000039 and should also come with a rubber boot which further helps reduce the chance of water ingress.
 
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