70 Duster Eagle Hemi Swap, No Spark!

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Wakeham70

Wakeham70

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So a little backround info on my 70 Duster project. I installed a new control freaks front suspension with a 5.7l Hemi out of a 2012 Ram. I used the origional PCM and Harness from the truck as well I used the cars origional 904 Trans.
All are bolted up and in place, fitment is good, but here comes my issue. I have the PCM wired and communicating with my mentor as well as HP tuners. I have fuel pump relay control from the PCM, ASD relay control from the PCM, injector pulse at each injector, but for some reason I have no PCM ground on any of the coils. I am hot on the BR/WT ASD wire, nothing on the ground side. Not sure why I would have no coil ground but yet have injector pulse...... Please Help!!!!
 
Sorry wish I could. I'd have to be there, have VERY good documentation, and just trace it out
 
As far as I know yes they do, as well as the injectors but I have injector pulse, also I have already disabled the SKIM. Which is why I am mindboggeled
 
I don't suppose you have a link to a wiring diagram?


Can you confirm you are getting cam trigger, etc?
 
Yes I am recieving Cam and Crank signal, and yes I have full access to tech authority's diagrams. Unfortunatly they seem to be somewhat simplified. See attachment
 

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Just a few thoughts.
Have you verified battery voltage is being supplied to all of the ignition coils positive terminals from the ASD relay?
Do you have a good ground to the engine and PCM?
Any trouble codes showing up?
 
Is your starter PCM controlled? I originally had mine wired with the original starter relay, and something similar was happening. The PCM needs to see starter command, even though the asd is powered in run, it won't fire the coils. As soon as I changed that, it fired right up.
 
Yes my starter is pcm controlled. I do not recieve any command to my starter relay from the PCM. What did you do if you dont mind sharing?

Thank you
 
I took my original starter signal from my ign switch and used it to command the PCM. The PCM then grounds the control side of the relay. If your car is set up this way and the PCM is engaging the starter, you're probably good. I had the ignition on, and then as far as the PCM was concerned, hotwired the starter. It didn't like it, the older cars once they saw a certain rpm they knew the starter was spinning the engine, but the anti double start is programmed into the PCM ( so you don't grind the starter while it's running). Just to clarify, is your car turning over with the key and not starting, or are you jumping the relay to get it to turn over?
 
Oh and double check that the neutral safety/clutch switch signal is grounded to the PCM
 
Neutral safety is grounded, but when you said "I took my original starter signal from my ign switch and used it to command the PCM" What pin did you connect the ign wire to? Also what year PCM and engine did you install?
 
Mine was 04-05 stuff, so it is probably a different pin than your newer one. I looked at the wiring diagram and followed what the factory hemi ignition switch did, just with the old one. There should be 12v to the PCM in start and run from the ign switch, and then 12v in start to a different pin only in start if I remember correctly. Your original ign switch will have 2 separate run feeds (because of ballast resistor), so connect both of those to the same ign run pin of the PCM, and then the start signal to that pin of PCM. Sorry I don't know the pins, hope that helps a little! Do you have a wiring schematic for your setup?
 
:sign3: The directions on my hotwire auto harness states that if you are using the factory60's and 70's Mopar ignition switch, you need to add a momentary switch for the starter to start. The Mopar switch turns off the power in the cranking position.
 
Not sure if the newer pcms are more sensitive, but I was able to not use a start button by making this brown jumper wire. When the ign switch moves from start back to run, there may be a short break in 12v, but my car doesn't notice it. My car has a hotwire 05 PCM with my home built harness, so things may be different. Mine has started for 1200+ miles so far!
 

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Here is what the 05 PCM wants to see from the ign switch.
 

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Here is the original 69 schematic, sorry my phone will only upload one pic per post. Mymopar.com has free schematics for old mopars, that would be the best bet. Like I said, not sure if this will work for a newer one. The monkeys on TV had this same problem, but during a commercial break they had it fixed, lol! Maybe a start button or a jumper wire?:glasses7:
 

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jrlegacy23 said:
:sign3: The directions on my hotwire auto harness states that if you are using the factory60's and 70's Mopar ignition switch, you need to add a momentary switch for the starter to start. The Mopar switch turns off the power in the cranking position.
Click to expand...

I remember Hotwire telling me this as well. I have a 2001 5.9 Magnum in my A-body with a 1998, 1500 Ram manual trans - non-security PCM, and the Hotwire hotrod harness; but I learned that I don't have to use the PCM's starter circuit, and use the original 1968 starter circuit to engage the starter as the PCM's starter circuit never worked in my application.
 
jbc426 said:
I remember Hotwire telling me this as well. I have a 2001 5.9 Magnum in my A-body with a 1998, 1500 Ram manual trans - non-security PCM, and the Hotwire hotrod harness; but I learned that I don't have to use the PCM's starter circuit, and use the original 1968 starter circuit to engage the starter as the PCM's starter circuit never worked in my application.
Click to expand...

That's true with magnum harnesses, but the hemi PCM has to see start signal. My magnum swapped 68 fury uses the old start circuit, so I tried it with the hemi, no go. The magnum PCM sees rpm when cranking to power the asd. The hemi PCM uses start signal, so although the engine is spinning at cranking rpm, there will be no power to coils and injectors. As soon as I let the PCM control the starter relay, it fired right up, plus I now have double start protection.
 
i havnt messed with my harness/car for a while but i was having a no spark issue also. I had no trigered ground to the coils. I may have to look into the switched/starter signal to the ecm and the neutral switch signal. I had coil power through the ASD...
thanks for this info guys
 
ralphie361 said:
Not sure if the newer pcms are more sensitive, but I was able to not use a start button by making this brown jumper wire. When the ign switch moves from start back to run, there may be a short break in 12v, but my car doesn't notice it. My car has a hotwire 05 PCM with my home built harness, so things may be different. Mine has started for 1200+ miles so far!
Click to expand...

You don't happen to have the harness drawn out do you? I've been thinking about making my own harness but without something to start me off, I'm feeling overwhelmed.

Thanks,

Riddler
 
Riddler said:
You don't happen to have the harness drawn out do you? I've been thinking about making my own harness but without something to start me off, I'm feeling overwhelmed.

Thanks,

Riddler
Click to expand...

I never drew the whole thing out originally, because I was in the experimenting phase as well! I would definitely help as much as I can, feel free to ask or pm me for more details. As long as you know what year engine, PCM, and harness you are starting with, I should be able to help or at least get you started. The way I did it was get the schematic for the PCM, and cross off the wires I didn't need. Once I cut those out, the harness was way smaller and less intimidating!
 

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I've got a 2004 ram 5.7 PCM with no skim, a 2006 6.1L hemi and a 2004 truck harness. I've been searching for a 6.1 harness.

I'm thinking I might have to start from scratch for a harness.....

Riddler
 
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