Engine will not shut down
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Engine will not shut down I am currently running into a wall and not sure where else to look. I have tried googling this issue but I have found no relatable symptoms.
The story:
I have a 04 LS1 GTO engine and ECU swapped into a 240sx. The engine starts and runs just fine, however when I cut power on the IGN3 (Pin 19 on C1/Blue), the engine will stumble in the slightest then continue to idle very smooth. I have verified that the controller battery lines are seeing 12v at all times through a 10amp fuse. I have verified that the IGN3 is ON when it is suppose to be ON and OFF when is suppose to be OFF. I haven't found any feedback to keep the controller ON. The two lines coming from the alternator are disconnected. When this "run on" happens, IGN3 has 0V but the controller obviously is still on. The fuel pump is still running (using the ECU fuel pump control).
I did a quick fix per say and just added the controller unswitched power lines to the switched power line. I would like to resolved why this is occurring and fix it accordingly. Any help would be greatly appreciated.
The story:
I have a 04 LS1 GTO engine and ECU swapped into a 240sx. The engine starts and runs just fine, however when I cut power on the IGN3 (Pin 19 on C1/Blue), the engine will stumble in the slightest then continue to idle very smooth. I have verified that the controller battery lines are seeing 12v at all times through a 10amp fuse. I have verified that the IGN3 is ON when it is suppose to be ON and OFF when is suppose to be OFF. I haven't found any feedback to keep the controller ON. The two lines coming from the alternator are disconnected. When this "run on" happens, IGN3 has 0V but the controller obviously is still on. The fuel pump is still running (using the ECU fuel pump control).
I did a quick fix per say and just added the controller unswitched power lines to the switched power line. I would like to resolved why this is occurring and fix it accordingly. Any help would be greatly appreciated.
Last edited by GETREKT; Apr 12, 2021 at 10:07 AM.
You mentioned the one wire going to the PCM. How are all your sensors, coils, and injectors getting power? They should all be on a switched ignition source as well. Sounds like they have constant power.
Thread Starter
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Ahh yes, I was waiting for this to be asked. Yes the Engine Sensors/Coils/Injectors are wired to a constant 12V. According to the schematic from AllData is shows they are connected directly to power. Pic attached
The "A" within the triangle goes to B+ which I assumed was battery power.
My question is why would OEM tie directly to battery? Is the PCM waiting for a BCM command to authorize a shutdown?
Thread Starter
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