RenoF250
Registered User
How many starts does it take to make the SES light reset? I think (hope) I set it with an overboost but it still has not gone off after about 6 start cycles.
SES Light
- Thread starter RenoF250
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RenoF250
Registered User
Checked the code it says P1211 which is an ICP issue suppsedly injectors are suspect. Considering I am loosing oil and suspecting them for that already I may have an upgrade in my future.
Doggy Daddy
Registered User
I have seen chips and programmers cause the 1211. If you watch the data stream on one of those trucks and run it hard the ICP shows unusually low even though the truck is making good power. I am certainly not an engineer and someone that knows more about how the chips works can correct me but I believe that the chip is boosting power by convincing the PCM that the Injection Control Pressure is lower than it should be and needs to be increased. My guess is that may go just a bit too far for just too long and then the PCM thinks there is a problem since everything else is reporting that the engine is working hard (accelerator position, RPM, boost).
It is annoying to have the light on but I don't think it harms anything. And I don't believe that injectors will cure it.
On the 2000 that I had the SES light would come on for overboost and then go out about a minute later (can't remember the exact timing) after boost was normal. You could put a zener diode on the MAP sensor to limit the boost that the PCM senses and not get the light ever for that.
Added in edit: Reno, I just noticed the Lab in your signature; you can see our pack HERE
It is annoying to have the light on but I don't think it harms anything. And I don't believe that injectors will cure it.
On the 2000 that I had the SES light would come on for overboost and then go out about a minute later (can't remember the exact timing) after boost was normal. You could put a zener diode on the MAP sensor to limit the boost that the PCM senses and not get the light ever for that.
Added in edit: Reno, I just noticed the Lab in your signature; you can see our pack HERE
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RenoF250
Registered User
Doggy Daddy said:
Thanks, that makes me feel better, especially since my oil level did not go down on the trip home, hopefully it is just the chip. I am still planning on buying an AutoEnginuity to check it out though.
Nice dogs, looks like you have quite a group there. You can't ask for a nicer more loyal dog than a lab. Mine is a bit dumb at times though.
RenoF250
Registered User
Okay, I just got the Autoenginuity scanner and I am wondering what the ICP#s should look like since I had a P1211. Currently they are ~600psi at ~9% duty cycle idling and max out at ~2,400psi at ~55% duty cycle. Does that sound normal?
Another thing I am wondering about is my exhaust back pressure is ~14.5psi idling and doesn't get below 19 psi when driving, is that right? That seems awefully high to me.
One more question, change in velocity for all cylinders is less than 1% except #8 which is near 2%, is that worthy of any concern? They all go to 0% with any kind of throttle.
Another thing I am wondering about is my exhaust back pressure is ~14.5psi idling and doesn't get below 19 psi when driving, is that right? That seems awefully high to me.
One more question, change in velocity for all cylinders is less than 1% except #8 which is near 2%, is that worthy of any concern? They all go to 0% with any kind of throttle.
