Swaping to EDIS Coils...

I

Innocent Fool

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Looks like a coil has blown out on my LS. With the cost of all these coils I've come to the conclusion that these COP coils have got to GO! The system itself if OK but the cost of the individual coils is ridiculous.

Basically I'm looking at replacing the COP coils with EDIS coil packs. I'm looking at using two coil packs from a V6 EDIS system. Each EDIS v6 pack contains three coils and costs about the same as a single COP so basically I'm getting all 6 coils for the same price as 2 COP. This makes allot of sense cash wise plus I can now mount the coil packs to a cooler location and where I can easily get to them if they need replacement. Replacing the COP coils on the v8 isn't so bad but I've got the v6 and I have to pull the upper intake off to get at the one side. This sux :(

Two EDIS coil packs will give me 6 coils which will be one for each cyl on my 3.0 v6. If I had the v8 I would probably run three EDIS v6 coil packs which would give me 8 coils for the cyls plus an extra coil to use as a spare if one dropped out.

From what I've seen all the EDIS coil packs are pretty much the same so I don't care what application they come from (I'm thinking a Ranger or Taurus). The only difference seems to be how many coils are contained in the pack and maybe the connector.

Electrically I'm thinking that I can power the coil packs using the same supply from the COP harness and use the same ground signal from the ECU in the harness to fire the coils when needed. Basically the ECU should not see any difference between the coils in the coil packs vs the original COP.

Main questions are:
- Do I have to worry about burning out the coil drivers in the ECU?

- The EDIS coils have two towers for spark plug wires to run the wasted spark setup. One tower is +(pos) the other is -(neg) Which one should I connect to the spark plug in the LS?

- Does any electrical guys have any advice?

- Am I on Crack?
 
The OEM coils go for about a 100K miles. Is that really so bad? Frankly, the coil pack on my Ranger seems to have about the same lifespan. (The Ranger is at 200K miles and is on its third coil pack.)

They moved away from the coil pack setup to the COP setup because it gives tighter control of ignition timing. If you put in two coil packs, you will have to tie the correct three of each six plug wires to dummy spark plugs that are grounded somewhere. The impedance of the coils won't begin to be the same as the COPs. The PCM will probably be very upset and may quickly be very damaged. The inductance of the plug wires will slow down the spark, and the PCM won't be expecting that. I can't see how this could be anything but less reliable.
 
I've been thinking of adding an extra sprocket on the back side of the drivers exhaust cam, that way I could just run a distributor I have laying around from an old Fox...

I love the look of spark plug wires!

the only thing holding me back is I don't quite have the right dremel bit to cut the necessary hole in the valve cover. I'm pretty sure I found the right kind of epoxy to mount the distributor to the valve cover...:shifty:
 
your ranger eats coils Joe..

many of those ford tower coils run out to 200k or more.

SHOs and early MN12 cougars (EDIS6) are starting to see coils have issues, but those cars are 20+ years old now.
the failure of EDIS8 tower coils, like in mark viiis, is almost unheard of.
though, due to the age, is bound to become more common like the SHOs.

the COP systems in newer VIIIs don't last as long, as expected.

but, as mentioned, EDIS is a waste spark system. COPs are not waste spark. so you'd have to deal with that. ground the other half and double the number of coils might work.

and if Mark VIII and Mustang guys can go from EDIS8 to COP systems, i'm sure you can go the other way. i'm just not sure how long the coil driver in the PCM will last.


as far as overall reliability in a stock system? EDIS8 is killing the COP systems hand down all day every day.
 
No need to double up, just need careful planning. The waste spark system is designed to have the coils on the opposing cylinders so the wasted spark hits during that cylinder's exhaust stroke. IMO, a better solution is to just use better coils. The stock coils are little tiny things compared to the coils used on other multicoil systems. I've said it before and I'll say it again, I'd look into using Chevy LS engine coils if I were keeping the car long term because the Chevy coils are over twice as large and can last hundreds of thousands of miles.
 
The problem with the COP (coil on plug) setup is heat. A better system would be coil near plug like what is on the GM LS engine family, but you need to use spark plug wires. The COP boots could become the spark plug boots, then run the spark plug wires out the back of the valve cover COP covers and mount the coils on the fender wall. That would be something like the setup on the 4.6L 4V engines in the Mustang Corba for a couple of years in the mid 90's before they went to COP's. Then there is the new primary wire harness that would be required to wire them up as well.

It seems like a big hassle. I would stick with replacing both the spark plugs and COP with new boots at a regular interval, say 50-75k miles.
 
Telco said:
No need to double up, just need careful planning. ...
Click to expand...

How to you propose to operate three coils each once every revolution from a PCM that is used to operating six coils each once every other revolution?
 
joegr said:
How to you propose to operate three coils each once every revolution from a PCM that is used to operating six coils each once every other revolution?
Click to expand...

LOL! you beat me to the question.
 
I'm thinking we'll need to double up the coils because the PCM will be looking for the feedback from the coil it wanted to fire. If we put the ground signals in parallel the coil should fire as a wasted spark but the PCM will likely report a misfire.

Right now the only real issue with using the EDIS coils would be possibly burning out the driver. An electronically triggered ground switch could be used to shunt the load from the driver but then the issue becomes how to tell the PCM that the coil actually did fire so it doesn't trigger a misfire code. Might be possible to send a simulated feedback signal to the PCM to make it happy. It wouldn't catch ANY misfires but I think we are all in tune enough with our engines to tell when there's an issue.

I really couldn't care if I've got some spark plug wires under the hood. I'm not in a car show and It's not getting graded. It may not be the most optimum solution but we're not running really high HP or high RPM here and we can afford to be somewhat less efficient. If I could replace my coils for 1/2 to 1/3 of what it would cost to replace the COP coils it would go a long way to making this car more enjoyable.

Now where's that crack pipe...
 
Innocent Fool said:
... It wouldn't catch ANY misfires ...
Click to expand...

Misfires are detected by the PCM looking at the acceleration/deceleration of the crankshaft relative to when each cylinder should fire. (Acceleration/deceleration is calculated by timing the crankshaft position sensor pulses.)
There is also an electrical check on the primary of each coil. If this check fails, a code is set and fuel to that cylinder is switched off.
 
just seems like a whole lot of figuring sh!t out just to maybe retrofit older less precise parts on a car instead of just replacing the parts the right way.


in less than the amount of time somebody would spend dicking around will all the things being suggested just to get it to work, I could take a could extra jobs and make enough cash to just go and buy the right part. I would also have the benefit of knowing that I am not going to burn my PCM up trying things. but thats just me...
 
Interesting... I assumed that the PCM was looking at feedback from the coil circuit to determine misfires. This might actually be better. I agree that it's probably better to just replace the coils with the correct parts and be done with it but where's the fun in that? :)

Thanks for all the feedback. I actually learned something today!
I'm going to continue looking into this when I get more time. If you see smoke on the horizon you know what happened...

Have a good one!
 
well, another project bites the dust.

They are always so excited too.

Can we put out a service builtin that just says, if you want to alter this car, buy a different car.
 
2002_lincolnLS said:
well, another project bites the dust.

They are always so excited too.

Can we put out a service builtin that just says, if you want to alter this car, buy a different car.
Click to expand...

sometimes you get lucky and the original owner didn't remove that sticker from the glove box...
 
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