94 2.3 no spark on 1 and 4 on intake side

Furbee86 · Jun 14, 2017

Breif history. Recently had whole bunch of issues but currently check enginw light with codes 224 and 998.
I have checked and 1 and 4 wires are getting no spark from the coil pack. 2 and 3 are sparking just fine. After googling i checked the wire thru the left side of connector with test light. Right side is switching like it should but the left isnt. Possible icm issue? I checked the icm and the bolt situation from prev owner made me not to confident. Top left towards pass side has a both that is way to long. Bottom left is empy and the the rights r both there. I tightened the 1 on top left. I could jiggle it and get shocked in the process. Would running a ground wire be a good start to this or is the icm just shot?

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Furbee86 · Jun 14, 2017

I should clarify when i said left i mean when looking from front so pass side. And right would refer to driver side.

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RonD · Jun 14, 2017

Ford uses a Waste Spark system.
Each coil pack for the 2.3l only has 2 coils inside.

Each coil sparks two spark plugs at the same time
1 and 4
2 and 3
These are the Matched pairs, 1 and 4 pistons are both at Top Dead Center(TDC) at the same time
2 and 3 are at TDC at the same time
This balances the engine

There are 3 wires connected to each coil pack
Center wire will have 12volts when key is on
Other 2 wires are Grounds, 1 for each coil, ICM controls these Grounds to spark each coil.

The ICM will only spark the Exhaust side coil pack while starter motor is active.
Intake side coil pack will start to spark when RPMs are above 300RPMs, so after engine starts.
So you should have No Spark while cranking engine on Intake coil pack

Common misconception about the dual spark plug 2.3l is that spark plugs alternate spark.
BOTH spark plugs in each cylinder spark at the same time
BOTH spark at compression TDC and Exhaust TDC, so twice every 4-strokes of the piston, one spark is "wasted" hence the name Waste Spark system
Dual spark plugs on opposite sides of the head in any engine makes for better MPG and efficiency, which was why it was added to the 4cyl Lima
Much harder to add to V6 or V8 engines since spark plugs need to be changed

Yes, ICM needs a good ground, common issue with this ICM is loose bolts and Ground
2.3l ICMs also failed, most auto parts stores had testers for them

If intake side 1 and 4 are not sparking while engine is running then that coil in the coil pack would be suspect, it can be tested with OHM Meter

Since one coil sparks two spark plugs the plugs have to be wired in Series
"+"-----------plug-------------plug-----------"-"
So a bad spark plug wire or spark plug would effect TWO cylinders

But this shouldn't cause running issues as long as Exhaust side 1 and 4 spark plugs are working

Furbee86 · Jun 14, 2017

RonD said:
Ford uses a Waste Spark system.
Each coil pack for the 2.3l only has 2 coils inside.

Each coil sparks two spark plugs at the same time
1 and 4
2 and 3
These are the Matched pairs, 1 and 4 pistons are both at Top Dead Center(TDC) at the same time
2 and 3 are at TDC at the same time
This balances the engine

There are 3 wires connected to each coil pack
Center wire will have 12volts when key is on
Other 2 wires are Grounds, 1 for each coil, ICM controls these Grounds to spark each coil.

The ICM will only spark the Exhaust side coil pack while starter motor is active.
Intake side coil pack will start to spark when RPMs are above 300RPMs, so after engine starts.
So you should have No Spark while cranking engine on Intake coil pack

Common misconception about the dual spark plug 2.3l is that spark plugs alternate spark.
BOTH spark plugs in each cylinder spark at the same time
BOTH spark at compression TDC and Exhaust TDC, so twice every 4-strokes of the piston, one spark is "wasted" hence the name Waste Spark system
Dual spark plugs on opposite sides of the head in any engine makes for better MPG and efficiency, which was why it was added to the 4cyl Lima
Much harder to add to V6 or V8 engines since spark plugs need to be changed

Yes, ICM needs a good ground, common issue with this ICM is loose bolts and Ground
2.3l ICMs also failed, most auto parts stores had testers for them

If intake side 1 and 4 are not sparking while engine is running then that coil in the coil pack would be suspect, it can be tested with OHM Meter

Since one coil sparks two spark plugs the plugs have to be wired in Series
"+"-----------plug-------------plug-----------"-"
So a bad spark plug wire or spark plug would effect TWO cylinders

But this shouldn't cause running issues as long as Exhaust side 1 and 4 spark plugs are working

So i just ruled out the coil being the issue. Swapped the front and rear. Exact same issue. Im starting to feel like icm or wiring..

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tomw · Jun 15, 2017

RonD:The ICM will only spark the Exhaust side coil pack while starter motor is active.

Unhh Uh.

Exhaust side plugs are sparked all the time. Intakes take the break, and spark on command.
If you disconnect the intake side, the engine will still run. It won't run w/o the exhaust side ignition operative.
tom

Furbee86 · Jun 15, 2017

I was incorrect. When i swapped them it started fine. But upon attempting to leave work i could feel it was misfiring bad. And had no acceleration. I need to figure out how to use my dmm so i can test the coil resistance. Ive never been good with the dmm

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Mark_88 · Jun 15, 2017

There is another user on TRS who recently went through months of diagnostics with one thing or another for misfires (on a 2.3) and found in the end it was a burned wire harness that was shorting out. Sporadic misfires were the problem there.

If yours is constant misfires or no starts then it could be a number of things other than coil packs or whatever but hopefully you can avoid the swap and snap that many find themselves going through.

What about the DMM do you need to understand? I learned how to test coils through a Youtube presentation when I was having issues with a misfire and it helped.

I found this one that might help...I watched just enough to see that it was easy to follow...

https://www.youtube.com/watch?v=XcmWa2Bt12U
Are you getting codes still or did they change to new ones?

Furbee86 · Jun 25, 2017

So i tested the resistance. Side 2 and 3 showed around 15k.other side i kept getting 1 even turned all the way up on my dmm. And still only codes are 998 and 224.

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Furbee86 · Jun 26, 2017

Mark_88 said:
There is another user on TRS who recently went through months of diagnostics with one thing or another for misfires (on a 2.3) and found in the end it was a burned wire harness that was shorting out. Sporadic misfires were the problem there.

If yours is constant misfires or no starts then it could be a number of things other than coil packs or whatever but hopefully you can avoid the swap and snap that many find themselves going through.

What about the DMM do you need to understand? I learned how to test coils through a Youtube presentation when I was having issues with a misfire and it helped.

I found this one that might help...I watched just enough to see that it was easy to follow...

https://www.youtube.com/watch?v=XcmWa2Bt12U
Are you getting codes still or did they change to new ones?

I dont know how i managed to overlook the most obvious thing. A few months back my serp belt broke while on the highway. When it did it frayed the wires at the connector to the coil pack. I taped them up and just when i replaced the belt. D'oh. I remeber both the red power wire and the ground for 1/4 were frayed pretty bad. Mainly the left 1/4 wire.. When i tested with the test light i got no signal from that wire. Now im racking my brain how to deal. Testing further away would give the same result if it is a ground wire that controls if i understand correctly. Would cutting damaged part of wire out and splicing in new wire further up fix at least partly the issue? I can take a pic later for more info

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Mark_88 · Jun 26, 2017

Furbee86 said:
I dont know how i managed to overlook the most obvious thing. A few months back my serp belt broke while on the highway. When it did it frayed the wires at the connector to the coil pack. I taped them up and just when i replaced the belt. D'oh. I remeber both the red power wire and the ground for 1/4 were frayed pretty bad. Mainly the left 1/4 wire.. When i tested with the test light i got no signal from that wire. Now im racking my brain how to deal. Testing further away would give the same result if it is a ground wire that controls if i understand correctly. Would cutting damaged part of wire out and splicing in new wire further up fix at least partly the issue? I can take a pic later for more info

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Depending on where the interruption is you might be able to just patch it...as long as there is no other damage that may be harder to see. My eyes are getting worse by the year after spending so much time staring at computer screens. Now I would need magnifiers and strong lights to inspect anything that small because the lighting under the hood is dismal at best.

Try patching first and if the problem doesn't clear up immediately do a more thorough search using better light.

if you can remove the harness completely that would be ideal. Just make sure to wrap it with the best protection you can afford and route it properly to avoid heat contact.

The EGR pipe on my 2.0 was supposed to be wrapped in a special heat resistant (asbestos) material but it often slid out of place and could melt through vacuum lines and wire coatings easily...

Speaking of vacuum lines...that's another possible cause with the way the lines are routed so close to the exhaust manifold and other hot spots...all it takes is a pinhole to make a difference in how the engine runs...

Furbee86 · Jun 26, 2017

Mark_88 said:
Depending on where the interruption is you might be able to just patch it...as long as there is no other damage that may be harder to see. My eyes are getting worse by the year after spending so much time staring at computer screens. Now I would need magnifiers and strong lights to inspect anything that small because the lighting under the hood is dismal at best.

Try patching first and if the problem doesn't clear up immediately do a more thorough search using better light.
..

I ordered a new coil pack since my testing showed that 1 was bad.im going down the path of replacing by lowest cost first) When prev incident happened both the power and the signal wire were damaged. Them touching for awhile could that have shorted the coil pack?
Or am i just going down the rabbit hole.

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RonD · Jun 26, 2017

New Coil pack won't hurt but make sure to fix those wires.
Hit wrecking yard and cut a good coil pack connector from the harness if yours is too short to splice
Ford V8's used same dual coil packs as the Lima dual spark plug engines

Furbee86 · Jun 26, 2017

RonD said:
New Coil pack won't hurt but make sure to fix those wires.
Hit wrecking yard and cut a good coil pack connector from the harness if yours is too short to splice
Ford V8's used same dual coil packs as the Lima dual spark plug engines

Would testing the signal wire @ the icm via test light show me if it is indeed wiring or would having that break near the coil harness not complete the circuit. Hopw that makes sense. Im trying to not waste money on icm if i can prevent it. Those dang things arnt cheap. I had a redneck thought. If both plugs fire @ same time could i splice a wire from the other signal wire on other coil pack over to this one?

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RonD · Jun 26, 2017

No, you can't/shouldn't run 2 coil packs from 1 wire, there is alot of current when ICM connects and disconnects those Ground wires.
That's why Points wore out(connecting and disconnecting coil's ground), and why electronic ignition modules run hot and need heat sinks, the transistors that replaced the points still have to deal with the connect/disconnect heat issue.

The Primary ignition coil is almost a dead short, .5 to 1.5 OHMs, 0 OHMs is a dead short, so when Ground is connected alot of AMPs can flow in to charge up the secondary coil

ICM can be tested at most parts stores

The two Ground wires on each coil pack need to be the same gauge from ICM to the coil pack, frayed wire is smaller gauge, so will cause misfires and could damage coil, heat build up

Intake side coil pack shouldn't have a ground pulse while cranking engine, it only starts working after engine is running, so not sure you could test ICM that way

Furbee86 · Jun 26, 2017

RonD said:
No, you can't/shouldn't run 2 coil packs from 1 wire, there is alot of current when ICM connects and disconnects those Ground wires.
That's why Points wore out(connecting and disconnecting coil's ground), and why electronic ignition modules run hot and need heat sinks, the transistors that replaced the points still have to deal with the connect/disconnect heat issue.

The Primary ignition coil is almost a dead short, .5 to 1.5 OHMs, 0 OHMs is a dead short, so when Ground is connected alot of AMPs can flow in to charge up the secondary coil

ICM can be tested at most parts stores

The two Ground wires on each coil pack need to be the same gauge from ICM to the coil pack, frayed wire is smaller gauge, so will cause misfires and could damage coil, heat build up

Intake side coil pack shouldn't have a ground pulse while cranking engine, it only starts working after engine is running, so not sure you could test ICM that way

just re-read your whole post. More clear now my steps. Step 1 repair/replace wire. New coil is on its way from rock auto. Do i take the icm out for them to test or leave it in and drive to auto store? Im gonna try and hit some junk yards to see what i can find for icm if still no luck. Im beginning to reget gettin a 23 yr old truck lol. (My wife is ready to sell it from under me. If only it was worth something) sucks this is my daily driver. And now my fuel economy has taken a crap on top of all this.

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94 2.3 no spark on 1 and 4 on intake side

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