FYI 8 Plug Ignition

[Yardbird]

Hey guys! Looks like my cold start problem is/was ignition related. I'm in process tuning up the ignition and changed the plugs on the passenger side last weekend. It was 10F this morning and the thing fired right up. Funny thing is, the clip for #1 plug came off the end of the wire when I pulled it and I didn't have a new one yet. (Just got the other four plugs and the wires today from RA.) I think that means that one cylinder is missing spark on compression and another is missing spark on exhaust, but it runs fine. Gas mileage seems pretty crap but it's got power and it isn't running rough. Maybe the computer is compensating. The Check Engine Light isn't on and the OBD doesn't show any stored faults.

So I'm learning a lot about this ignition system that I'm going to document in this thread. First is a link to an article on diagnosing Waste Spark DIS systems. It's got a good explanation/diagram of how the system works and illustrations of various scope waveforms. It's a PDF than I might could upload, too, but I don't know how that would work and it might not be ethical.

http://www.motor.com/magazine/pdfs/071999_06.pdf

 

[PetesPonies]

Why do people want to continue with the "wasted spark" term?? There is no spark on the exhaust stroke for "emissions". There is NOT. Every engine in the world with a coil pack feeding two cylinders has what is referred to as wasted spark. But the spark that is "wasted" is so small because there is no compression ,wastes so very little . . it is nothing in the grand scheme. The fact that there are two plugs per cylinder has NOTHING, NOTHING, NOTHING to do with it being a wasted spark ignition. This is where the ignorance creeps in and sets up home. The two plugs fire just slightly apart from each other. Other than engine startup, they fire together on the compression ( albeit slightly behind ) and together again on the exhaust stroke ( albeit a tiny bit of voltage in this situation) . Wasted spark was used on motorcycles back in the 60s just for an example. Stop mixing up wasted spark and dual plugs into one ridiculous term that for used for 2.3 engines !!!

 

[Mikel89us]

Waste spark has everything to do with this ignition, it is infact, a waste spark system. Actually its two waste spark systems, and its called waste spark because that's what it was called when it was first put into production all those years ago.

Its actually called waste spark because in a normal single coil engine, the electricity flows through the ground, the block, the head and spark plugs and wires. With the "waste spark" setup, the considered the travel through all that wasted energy, and decided to make the path less of a waste by also firing on exhaust to potentially help burn any fuel that is left over. Does it work like that? NO. But that was the concept.

The other advantage to it is the lack of need of a cam sensor. When you fire the two companion cylinders at the same time, you don't need to know where the cam is, only where the crank is. It was/is much cheaper to build, but slightly less efficient. It is not ignorance to call it that, it is the accepted term.

He is correct though in assuming that if its not firing on one plug the other is also not firing, and if you have a different combustion on those two cyl, it will cause a difference in power on the two halves of the engine and cause it to run a little rough.

 

[PetesPonies]

Mike are you fully understanding what I an saying? I taught this info for many many years. I'm trying to set the record straight on here. I'm tired of reading posts from people who don't get it. Wasted spark is on EVERY engine where a coil is responsible for firing two cylinders without a distributor. It has nothing to do with dual plugs. Ignorant posts abound with those two different subjects, inter mixed for a totally in accurate understanding.

 

[Mikel89us]

He's not wrong though, every statement he made is on the money. When cyl one is supposed to fire on compression, cyl 4 fires on exhaust. So he is right about that. It also works the other way, when 4 is supposed to fire on compression its won't if cyl 1 has a bad plug wire on the same side. I think you are misunderstanding what he means.

Luckily for him, this is a dual waste spark system, and he has another set of coils and plugs that fire as well. Otherwise it would probably not run.

 

[Kenneth S]

Mike are you fully understanding what I an saying? I taught this info for many many years. I'm trying to set the record straight on here. I'm tired of reading posts from people who don't get it. Wasted spark is on EVERY engine where a coil is responsible for firing two cylinders without a distributor. It has nothing to do with dual plugs. Ignorant posts abound with those two different subjects, inter mixed for a totally in accurate understanding.

Ford did away with the distributor, and went with a crank position sensor, dual coil packs in 1989 2.3 Ranger, and later engines (1991 in the 2.3 Mustangs) when they went to the two plugs per cylinder cylinderhead design. It's exactly the same waste fire ignition system just like what's on a motorcycle, you have been misinforming everyone you have taught for many many years.

You should read this http://rockledge.home.comcast.net/~rockledge/RangerPictureGallery/DIS_EDIS.htm

 

[simpler=better]

All I know, is that when I tore the plugs wires on one bank I was able to drive to the store with no problems on the other bank. That's why I love my 8plug system-you can still get where you're going if a bank dies.

 

[PetesPonies]

Ford did away with the distributor, and went with a crank position sensor, dual coil packs in 1989 2.3 Ranger, and later engines (1991 in the 2.3 Mustangs) when they went to the two plugs per cylinder cylinderhead design. It's exactly the same waste fire ignition system just like what's on a motorcycle, you have been misinforming everyone you have taught for many many years.

You should read this http://rockledge.home.comcast.net/~rockledge/RangerPictureGallery/DIS_EDIS.htm

I am the one who has been saying this is the same ignition as motorcycles have been using for 50 years. I know exactly what I have been teaching, you don't know how to read for comprehension. Re read my posts. My point is more than just this thread. There have been people posting about lost spark ignitions and mixing it with dual plug engines. as if these two things are related . They are NOT. The unknowing think the extra plug is for the "lost spark". It is not. This is what I have been preaching about. The two have nothing to do with each other.Lost spark is on probably 80% of the cars on the highway today. It's not some "crazy" Ford idea and you can run your plug wires differently and make it better LOL. That is what has been posted many times and I jjst want to make sure people don't believe this crap. So re read what I posted and see that I am not the one who is wrong here. Jeeshhh . . .