87 notch/weird accel coil problem

Hey guys, Glad to finally join up since I do a lot of reading off these forums. I'm having a strange issue running a particular ignition coil. For a little background as it pertains, I'm running a MSD billet dizzy with motorcraft tfi module, msd blaster coil, 8mm ford racing wires, and it is all under the control of the ProM efi control system. In an attempt to freshen spark I tried to replace a my 15 year old MSD coil with an Accel E-core Super coil. I thought the first one out of the box had issues as after replacing the car would suffer severe detonation above 3000 rpm, and even the tachometer would go haywire. Under 3 k all was well. I returned for another and I am having the same issue. At approximately 3000-3500 rpm It spits sputters and det knocks. Base time is set at 10* with total advance at 36*. No evidence of cross fire under cap, and I even tried another cap and rotor. Everything I'm running currently is very low mile. Wires are all good, no bright lights in the dark. Spark plugs are new gapped at .030. Does anyone know if the Accel coils are known for being electrically noisy? It's as though my pip signal goes nuts. I have the MSD coil back on the car and all is well, but I can't be happy without knowing why this is happening. Does MSD have an issue playing nice with other brands? Or is there something else I'm missing? Accel coil ohms to its rated values at .04 primary and 8.8 k secondary.
 
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It does look good. So your saying in terms of electrical noise? I know it took me 3 to get one that worked, but once I finally did get one that worked it produced a perfect signal. Elaborate please.


I could do that but it would still be only speculation on my part. Instead, I will direct you to JR's checklist. It will lead you to the failed component(s):

https://www.stangnet.com/mustang-fo...-checklist-for-fuel-injected-mustangs.787471/

Granted, some of those procedures won't apply to you due to your aftermarket ECU but for that, perhaps @a91what can lend some assistance.


In my own jaded opinion, MSD products were designed to be shot off the top of fence posts. That aside, there is no better distributor made for a small block 302 than the one made by Ford.
 
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Also depending on the tfi you are running you could have issues, the black ones are ccd (computer controlled dwell) they will not play well with low resistance coils if the ECU does not properly saturate the coil. IE. The pro m is not controlling the dwell. This causes weak spark
 
I rebuilt an MSD billet distributor with a motorcraft pick up. With the cap off you should be able to look down below the metal part the rotor sits on.

That piece the rotor sits on is read by the pick up. The pick up itsslf should not look powdery or soft. Its not super hard to replace but dies involve removing the distributor and pressing the gear off. The pick up in the MSD is the same as the pick up for a stock 5.0.

My MSD distibutor has been working for about 15 years.... no problems. I'm sure I've put at least 60k + on it.
 
I rebuilt an MSD billet distributor with a motorcraft pick up. With the cap off you should be able to look down below the metal part the rotor sits on.

That piece the rotor sits on is read by the pick up. The pick up itsslf should not look powdery or soft. Its not super hard to replace but dies involve removing the distributor and pressing the gear off. The pick up in the MSD is the same as the pick up for a stock 5.0.

My MSD distibutor has been working for about 15 years.... no problems. I'm sure I've put at least 60k + on it.
If by same you mean cheapest possible chinne knockoff
 
Sorry for delay, I haven't had much time. All I've had time for is to compare the msd coil resistance against the accel. MSD primary higher at .9-1. Secondary in at 4k. That seams comparable to what they currently offer.
Likely a bad pip in the distributor.
I think that is starting to make sense. If I understand the PROM ecu operation correctly , "big if", The tfi is out as it now only serves to pass signal to the ecu and has no effect on fire. The PIP signal is pristine and everything checks at Idle but I'm not sure what it looks like at high rpm under load. Perhaps a tired old coil has masked a problem that was revealed with fresh spark. If weather permits I'll data log it this weekend with both coils. Thanks for the direction.
 
????? Another crap accel coil ??????????
Ran a log on pip count and whatever else I thought would reveal the pip signal. No difference between coils. But on a counter point..... I switched back to my 28 year old stock distributor and of course it runs better than with the MSD.
MSD is like an abusive lover..... you think to yourself time and time again..... maybe they changed.....maybe it'll be different this time:rolleyes:
As far as the coil I'm at a loss ready to say it's 2 bad coils out of the box. Spark on the accel looks the same or worse than the msd to me. Jumps 3/8" no problem but looks orange even on a plug jumping .030.
Not sure what else I can check... the coil is the only variable left.
With the pip signal showing good with no discernible gaps in count, then wouldn't that rule out electrical noise?
 
The stock distributor runs better than the msd, but the car still will not run with the accel coil. At 3500 rpm it breaks up,spits, bucks ,and detonates. The fluttering I was seeing was on the dashboard tach. The readout from the ecu doesn't do the same jumping around. I'll see what I can do about posting the log file. Beware, i'm pretty new the the software.
 
It's ok they are 2 separate signals, ECU gets the pip, tach gets the negative side of the coil. I assume you have swapped the tfi to try a new one right? The tach is seeing the coil drop...

Try this pull the spout and set the timing locked at 26* see if it still breaks up.