What is a good replacement ICM?

[macdude443]

Just thinking out loud. The oem setup has the distributor pickup signal going from the distributor to the ECM and then to the ICM and controls timing. I wonder if you can keep the ECM and still use a CDI like an MSD or the like and still have the ECM control timing. The CDI won't know the difference if the signal is coming directly from the distrib.utor or the ECM.

That's what I'm thinking. Obviously you can switch the ICM to a direct connection to the pickup when a bypass is done, so the trigger signal is no different.  The only difference is the wiring. The ECM sends the trigger signal to the Orange wire via a light green harness wire. The violet is left unused.

The bypass connects the violet and orange at the ICM directly to the dist pickup.

The MSD would need to be triggered using only the Orange wire, like the ICM is when the ECM is in the loop. I'm not sure if it'll work with the violet disconnected. They have a tech support line. Time to call I guess.

[carnuck]

The misfire may have been from the ignition module overheating from firing a non-stock coil. Did you do a big cap (AKA Team RUSH) upgrade? The higher spark from non-stock coil can jump between terminals. When warm the bits of carbon and metal inside the cap will "stand up" from magnetism and make a spark pathway. I had major issues with a stock ignition rotor allowing spark to bypass with a Dodge electronic ignition coil swapped in. A new quality brand rotor fixed it.
   I would either go HEI (Skip White is ready to go in when I have time) or go retro. You can remove the internals of the Eagle Motorcraft dist and swap in the points setup from a Ford six of early '70s vintage. Points will run an MSD 6A and if lubed correctly, may never need changing again.

[macdude443]

The misfire may have been from the ignition module overheating from firing a non-stock coil. Did you do a big cap (AKA Team RUSH) upgrade? The higher spark from non-stock coil can jump between terminals. When warm the bits of carbon and metal inside the cap will "stand up" from magnetism and make a spark pathway. I had major issues with a stock ignition rotor allowing spark to bypass with a Dodge electronic ignition coil swapped in. A new quality brand rotor fixed it.
   I would either go HEI (Skip White is ready to go in when I have time) or go retro. You can remove the internals of the Eagle Motorcraft dist and swap in the points setup from a Ford six of early '70s vintage. Points will run an MSD 6A and if lubed correctly, may never need changing again.

It isn't a stock coil, as I mentioned.  I still have the stock coil.  I did the big cap upgrade with quality brass cap, etc.  Are you saying I need to go back to the factory small cap?  I'm confused.  I haven't had the problem since putting my old module back in.  That tells me that the new module was acting flaky when it got hot.  If the old one doesn't mind the big cap and MSD coil, shouldn't I be ok?  The plugs are currently NGK and factory gapped at .035.

[eaglefreek]

I know this is getting sidetracked with MSD, but I was looking at a diagram and maybe the spark output wire from the ECM(MCU) could go to the white wire of the MSD which is typically triggered by the points when using a points distributor or just run it to the MSD violet wire like it normally would and leave the MSD green wire unhooked.

[macdude443]

I know this is getting sidetracked with MSD, but I was looking at a diagram and maybe the spark output wire from the ECM(MCU) could go to the white wire of the MSD which is typically triggered by the points when using a points distributor or just run it to the MSD violet wire like it normally would and leave the MSD green wire unhooked.

This is what I was going to call about.  I just haven't had the chance.  It's a good idea for down the road, but I'm sure I can get a decent module somewhere.  The Ford guys run these Duraspark units still and it is even a known upgrade from points.

[carnuck]

The big cap is needed with a high output coil. I didn't know you did that already.

[macdude443]

The big cap is needed with a high output coil. I didn't know you did that already.

Yeah, sorry.  I should have mentioned.  I had the plugs gapped to .045 like the TR instructions recommended.  When I had the issues with pinging I started running the NGK plugs, which have two ground straps and factory set to .035, so I didn't mess with the gap.

- Blaster 2F coil (with original horse-shoe connector - have a replacement connector I can splice on if needed)
- ECM operational, stepper connected and operating, brand new EGR valve, charcoal canister working, new cat, sol-vac adjusted and working
- Ignition system wiring is stock
- Team Rush upgrade (big dist cap with brass terminals, taller dist. rotor, 8mm plug wires)

[eaglefreek]

I wonder if you could melt the rubber out of a Duraspark and repair the damaged component(s).

[macdude443]

I wonder if you could melt the rubber out of a Duraspark and repair the damaged component(s).

I've thought about it. If I find a bad, original AMC/Motorcraft unit.

[Nightpath]

They can be melted out, with a heatgun or in the oven, but you take the risk of damaging other parts.

The original ignition system had problems from the get go, and newer manufactured parts are mostly rebranded Chinese junk. I bought a new starter solenoid and it caused so many issues I couldn't keep the car going. Pulled one from a junked Eagle and the car worked great.

Your problems could be a small vacuum leak causing timing problems, buggy ECM when it heats up, or a intermittent wire. If you're getting pinging when putting the pedal to the metal than your timing is off.

Now, on another note, a GREAT modification is the HEI ignition...easy to install and run, and you just disconnect the stock ignition system and put the distributor in the trunk in case the HEI poops the bed. It runs hotter and has way less issues. A new set of wires, plugs and you're ready to roll, and it also keeps the stock parts.

In saying this, I may have a spare ICM laying around (can not verify if it works, but all the ones I pulled I swapped out when troubleshooting and iirc they worked). If I do it's yours for the price of shipping, then you can try it out and dig into it. Shoot me a pic of your ICM wiring as I think there were 2 different connectors.

[macdude443]

I realize how wonderful the HEI is to most people (I did this in my SX/4).  But I want to keep the wagon as stock as possible.  I did the ECM Test on it until I gathered the parts to fix it the right way. I don't want to gut my ignition system as that is not my goal with this vehicle.  I have been very happy with the performance since re-connecting the computer, I would just like some opinions on a good replacement Duraspark module.  If there are no good replacement DS modules known on this earth, then I'll go Stealth HEI next in order to keep my distributor and still have the ECM in the loop.

There is a slight timing problem, but it seems to vary slightly based on the ignition module I install.  The old Wells unit pinged and the newer one doesn't.  It simply flakes out randomly.  I've checked for vacuum leaks everywhere.  All diaphragms hold vacuum.  All new hoses everywhere.  New carb gaskets, new intake/exhaust gaskets.  It idles perfectly at 600RPM in drive.  No stalls coming to a stop or turning hard.  It's not the fuel filters (new) and the tank sock is removed.  All fuel lines new.  Check valve in return line, 3-port filter, right side up.  Timing chain is new as well.  The distributor is an OEM unit I cleaned up.  It doesn't appear the springs were ever touched.  It moves freely and smoothly with no noticeable slop.  13* centrifugal advance slot is in use.  It seems to jive pretty well with the advance curve band in the '86 TSM.  I've also adjusted the vac advance with a gauge to best match the TSM vac advance curve.  I'm quite sure it's the newer module causing the missing.  I've driven it 100 miles now will the old Wells module re-installed and it hasn't acted up once.

I got my Motorcraft module in yesterday so I'll put that on and see what happens.  If I get pinging I'll back off the initial timing 2* and call it a day.  If this module is junk, too maybe I'll change my path and go with something aftermarket.  Maybe I'll try the NAPA Echlin module, but I would hope that an actual Ford branded part wouldn't be complete crap, even if made in China for Ford.

They can be melted out, with a heatgun or in the oven, but you take the risk of damaging other parts.

The original ignition system had problems from the get go, and newer manufactured parts are mostly rebranded Chinese junk. I bought a new starter solenoid and it caused so many issues I couldn't keep the car going. Pulled one from a junked Eagle and the car worked great.

Your problems could be a small vacuum leak causing timing problems, buggy ECM when it heats up, or a intermittent wire. If you're getting pinging when putting the pedal to the metal than your timing is off.

Now, on another note, a GREAT modification is the HEI ignition...easy to install and run, and you just disconnect the stock ignition system and put the distributor in the trunk in case the HEI poops the bed. It runs hotter and has way less issues. A new set of wires, plugs and you're ready to roll, and it also keeps the stock parts.

In saying this, I may have a spare ICM laying around (can not verify if it works, but all the ones I pulled I swapped out when troubleshooting and iirc they worked). If I do it's yours for the price of shipping, then you can try it out and dig into it. Shoot me a pic of your ICM wiring as I think there were 2 different connectors.

[carnuck]

Do the stealth swap. Use an OEM AMC box and melt the old stuff out and use the box as a heatsink for HEI module inside. It's been done.

[macdude443]

Do the stealth swap. Use an OEM AMC box and melt the old stuff out and use the box as a heatsink for HEI module inside. It's been done.

Yeah, it's on my list of summer projects to try.

[amcfool1]

hi, going through a rebuild right now, as far as  ICMs, the Wells seems to be the best quality. Look for parts made in Mexico, rather than in China or other far east manufacturers. AFAIK, no more American made parts. Coils, again, look for Mexican made, supposed to be the same design as the old Illinois factory that closed and moved there. Stay away from all "brand" type coils, MSD, Accell, etc, unless you know the place of manufacture. The Napa "universal" coil, UC12, is still a good choice. Taylor coils are still made in US, but finding right resistance is tricky. Long story short, don't look for bargains, do your homework, and buy the best, (not necessarily the most expensive) parts you can. Do NOT get epoxy filled coils, the kind the offroad guys like. The oil in an oil filled coil is there for a reason. to cool it. Epoxy won't leak out, true, if turned upside down,but, it will overheat and break down, so, don't drive upside down! good luck y'all, gz

[JayRamb]

I bought a new one, made in USA, and it lasted 1 month. I took it off in my troubleshooting and the entire back side, the black, was like fresh black silicone smeared on the underside. It was ruined. So, I went on Rock Auto and bought two, one as a back up that I can use if it does that again. The newer, lastest one was made in China. So...there you have that!