PCM communication issues
Lead Driver
Joined: Oct 2005
Posts: 6,129
Likes: 1,919
From: Ponca City, OK
Will go over the harness tomorrow when I get off work.
1- would having an electrical issue on just 2 of the cylinders cause a no start condition? I mean in reference to the two Cylinders that were way out of spec.
2- why would the icp being plugged in make the check engine light not stay on (KOEO) like its supposed to?
1- would having an electrical issue on just 2 of the cylinders cause a no start condition? I mean in reference to the two Cylinders that were way out of spec.
2- why would the icp being plugged in make the check engine light not stay on (KOEO) like its supposed to?
ICP unplugged will always throw a light. Not all codes maintain a light until cleared, a lot of codes will only throw a light when the issue is recognized but will turn off shortly after. Sounds like pcm is doing what it's programmed to do in that regard.
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5th Wheeling
Joined: Jul 2014
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I've read here that a communication issue w/ even 1 injector can cause the idm to shutdown the entire bank. Is that likely your issue? IDK, but if there is any kind or communication between the pcm and idm that will definitely cause a no start.
ICP unplugged will always throw a light. Not all codes maintain a light until cleared, a lot of codes will only throw a light when the issue is recognized but will turn off shortly after. Sounds like pcm is doing what it's programmed to do in that regard.
ICP unplugged will always throw a light. Not all codes maintain a light until cleared, a lot of codes will only throw a light when the issue is recognized but will turn off shortly after. Sounds like pcm is doing what it's programmed to do in that regard.
No sir not what im saying.
Normally with the key in the on position - the service engine light will stay illuminated.
If the ICP is plugged in - once you turn the key to the on position - the service engine light comes on for 1 second and then goes out. Which is abnormal as far as i know.
If i go back and unplug it - the light comes back on like its supposed to.
Key on engine off.
Lead Driver
Joined: Oct 2005
Posts: 6,129
Likes: 1,919
From: Ponca City, OK
Your dc% looks fine to me. That number is directly dependent on the icp and what you and the pcm are asking for at the time. Max dc% w/out tuning is around 67% I think, so if you are seeing it stop climbing at 46% then the pcm is seeing the pressure it wants so no need to push the ipr harder.
Lead Driver
Joined: Oct 2005
Posts: 6,129
Likes: 1,919
From: Ponca City, OK
No sir not what im saying.
Normally with the key in the on position - the service engine light will stay illuminated.
If the ICP is plugged in - once you turn the key to the on position - the service engine light comes on for 1 second and then goes out. Which is abnormal as far as i know.
If i go back and unplug it - the light comes back on like its supposed to.
Key on engine off.
Normally with the key in the on position - the service engine light will stay illuminated.
If the ICP is plugged in - once you turn the key to the on position - the service engine light comes on for 1 second and then goes out. Which is abnormal as far as i know.
If i go back and unplug it - the light comes back on like its supposed to.
Key on engine off.
It's a Van Gogh
Joined: Feb 2010
Posts: 7,813
Likes: 1,335
From: Elk Grove, CA
Sounds like normal operation. When keyed on the dash will briefly illuminate all lamps so you can check if any are burned out. The CEL is included in that. Then the CEL will remain lit only if there is a code stored, or in this case a sensor is disconnected. If the PCM sees all sensors and there are no codes the CEL has no reason to be lit. Only the Check Gages and Battery lamp will remain lit because the alternator is not working with the engine off. Or maybe I am misunderstanding what you are seeing?
The pin numbers you reference above with the giant 600 ohm resistance on pin 6; what connector is that? That resistance looks like a problem.
The pin numbers you reference above with the giant 600 ohm resistance on pin 6; what connector is that? That resistance looks like a problem.
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5th Wheeling
Joined: Jul 2014
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Sounds like normal operation. When keyed on the dash will briefly illuminate all lamps so you can check if any are burned out. The CEL is included in that. Then the CEL will remain lit only if there is a code stored, or in this case a sensor is disconnected. If the PCM sees all sensors and there are no codes the CEL has no reason to be lit. Only the Check Gages and Battery lamp will remain lit because the alternator is not working with the engine off. Or maybe I am misunderstanding what you are seeing?
The pin numbers you reference above with the giant 600 ohm resistance on pin 6; what connector is that? That resistance looks like a problem.
The pin numbers you reference above with the giant 600 ohm resistance on pin 6; what connector is that? That resistance looks like a problem.
That is on the IDM connector itself.
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