# Wastespark to coil on plug conversion..

#### Brobullet

Joined Oct 29, 2019
2
Hello..
Im converting my car wastespark ignition to a coil on plug type ignition, the thing is the ECU has already with built-in igniter circuit.. i know the C.O.P also has a built in igniter too..
The question is.. how do i wired it so the coil dont get burn toast.. should i pull some resistor or a diode to ground or something... ?

Just a kid..

#### crutschow

Joined Mar 14, 2008
23,502
How will you generate the individual spark signal for each plug?
I assume you want to eliminate the waste-spark signal.

What is an "igniter circuit"?

#### shortbus

Joined Sep 30, 2009
7,078
What is an "igniter circuit"?
What many talking on the weird wide web in car forums are calling the mosfet driver circuit to turn the coil on and off to make a spark.

#### shortbus

Joined Sep 30, 2009
7,078
Hello..
Im converting my car wastespark ignition to a coil on plug type ignition, the thing is the ECU has already with built-in igniter circuit.. i know the C.O.P also has a built in igniter too..
The question is.. how do i wired it so the coil dont get burn toast.. should i pull some resistor or a diode to ground or something... ?

Just a kid..
How are you going to pull the single cylinder response from your waste spark(WS) ECU? Using the WS ECU you will have two cylinders at a time firing still. What make and model and engine are you trying this on?

#### DarthVolta

Joined Jan 27, 2015
150
So older engines with more than 1 cyclinder, would just fire all the sparkplugs at the same time, just to make it simpler. I only learned that yesterday.

Does a distributor fix that problem ? So s.p.'s only fire at the right time in each cycle ?

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#### crutschow

Joined Mar 14, 2008
23,502
Does a distributor fix that problem ?
It's not a significant "problem" but yes, a distributor only fires one plug at a time.

#### Brobullet

Joined Oct 29, 2019
2
How will you generate the individual spark signal for each plug?
I assume you want to eliminate the waste-spark signal.

What is an "igniter circuit"?
Well .. its still a 2x2 wastespark firing..
but with an individual coil..
Igniter on the other hand, is just a power transistor (mosfet, IGBT etc..) to run the coilpacks...

Almost all c.o.p has an igniter (power transistor) built in..

#### crutschow

Joined Mar 14, 2008
23,502
its still a 2x2 wastespark firing..
but with an individual coil..
Is there some advantage to that?

#### shortbus

Joined Sep 30, 2009
7,078
Almost all c.o.p has an igniter (power transistor) built in..
That depends on the system whether it is a 2 or 3 wire system.

#### bwilliams60

Joined Nov 18, 2012
1,199
1) What year/make/model and engine are we working on?
2) Why.? Just curiou what the benefit of this would be?
3) Are you planning on firing two coils at a time and if so, where do you plan on pulling the trigger signal from?
4) If you are planning on using individual coil firing, where are you getting the signal from?
On a waste spark system, the ECM usually generates a signal to an ignition module telling it when to fire the coil based mostly on cam and crank signals. On COP systems, the ECM generates a signal to fire each coil individually.
Not trying to rain on your parade, seen stranger things happen on here, just curious as to the logic behind it.

#### Papabravo

Joined Feb 24, 2006
12,500
I may be in the minority here, but I think "just a kid" ought to have a MUCH better idea of what hes is doing and why before turning a functional vehicle into a BRICK. In the middle of the last century when you could buy used car for $100.00, doing stuff like this was both possible an educational. When a late mode used car costs$15,000.00 you're takin a much bigger risk that something will go wrong that will be expensive to impossible to fix. BE CAREFUL

#### bwilliams60

Joined Nov 18, 2012
1,199
I am on the same page with this one @Papabravo . That is why I am asking the all important question.....Why?? I don't think he knows what he is in for going down this road. I am looking at ECM's and harnesses to start but still not sure what the plan is so can't really comment until I do.

#### Papabravo

Joined Feb 24, 2006
12,500
I've heard from engineers at Ford and FCA that ECM's have security features that make modifications of any kind difficult to impossible. Manufacturer's could potentially incur huge liability for an owner making a modification that caused death or injury for any of a number of reasons. As I understand it the ECM can talk to sensors on the network, verify they are there and run integrity checks. Disconnect one and you get a brick.

#### bwilliams60

Joined Nov 18, 2012
1,199
There are a lot of back door options that are available but we don't talk about them on this forum. There are a few who can circumvent ECM information but as you said, you are liable for any changes you make to said ECM so you really need to know what you are doing. I don't think the OP is at that level. The newest PCMs are one write so the security levels are really difficult to bypass. There are billions of dollars being spent on the security industry in automotive right now. It is crazy the things they do to make our vehicles secure. But whatever they do, there is always someone else out there that can undo it. And then the car industry pays them huge money to work for them and they have a job for life

#### shortbus

Joined Sep 30, 2009
7,078
just curious as to the logic behind it.
Some people on the forums seem to think that just a change like this will take their 4cyl in to a V8 power wise. Most are "just a kid" but sadly many are old enough to know better, or should know.