Nissan NSD40A coil replacement

MikeMaxx

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Nov 26, 2023
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What's the work around for replacing the old 2 primary wire coils that feed back to the ECM on a 2003 40hp TLDI? No new stock available and don't want to gamble on used take offs. I'm not afraid to McGyver something myself. Thanks!
 

MikeMaxx

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Nov 26, 2023
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For reference, here's my measurements;
Primary Secondary
#1 3 Ohms 17.2K Ohms
#2 4 Ohms 16.6K Ohms
#3 3 Ohms 17.4K Ohms
 

MikeMaxx

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Nov 26, 2023
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Seems like the resistance readings are OK on the 3 coils. I'm now questioning the ECM trigger voltage output. That and the fact there's no tach or diagnostic LED output. I haven't probed the harness close to the ECM socket yet for the tach/LEDs or to find out what the coil output signal is yet. Could be a defective ECM.
 

MikeMaxx

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Nov 26, 2023
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40A TLDI status update.. 2 open air injectors, no resistance-no click. All fuel injectors click and 2.5 ohms on 1 air injector and all 3 fuel injectors. Sourcing the air injectors and a means to pressurize the fuel injectors to clean them.
 

MikeMaxx

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Nov 26, 2023
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Does anyone know if a "noid light" will work to determine if there's a trigger signal from the ECM for the injectors?
 

MikeMaxx

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Nov 26, 2023
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12
Update...I found a 90A TLDI for parts or repair. Only missing the fuel pump housing and vapor separator housing. Supposedly would run but not idle. I'll scavenge from it for the 40A. I'll also swap parts to see how it runs if possible. The weather will be an issue for the next week here in Michigan.
 
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