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Posted
On 3/9/2022 at 12:03 PM, Deeman65 said:

Did you figure out the problem? I have the exact same issue with my 2011 2500 and could use some help 

I have not. I can’t for the life of me figure it out. Hoping someone will buy it how it sits. 

  • 2 weeks later...
Posted

ok this 2011 2500hd is pissing me off im at a loss im the guy every one brings vehicles to when they cant figure it out this one has me stumped  Iv been doing this for 22 years and have never installed a transmission and then had electrical or fuel issues has anyone figured this out 

Posted
1 hour ago, lnb said:

ok this 2011 2500hd is pissing me off im at a loss im the guy every one brings vehicles to when they cant figure it out this one has me stumped  Iv been doing this for 22 years and have never installed a transmission and then had electrical or fuel issues has anyone figured this out 

Yep same issue. My father has been an ASE master Tech for more then 30 years. Cannot figure it out to save our lives. I’ve replaced everything I could even think about and nothing has worked. I have no idea what it could possibly be. 

Posted

It has to be some form of sensor issue but I can’t figure it out. I’ve checked wiring between everything and even grounded the computer and still nothing. I don’t understand how out of no where it started this and no matter what I have done or tried it doesn’t fix it 

Posted
13 hours ago, casey.mikl said:

It has to be some form of sensor issue but I can’t figure it out. I’ve checked wiring between everything and even grounded the computer and still nothing. I don’t understand how out of no where it started this and no matter what I have done or tried it doesn’t fix it 

Parts wear.  Connections rust.  Heat cycles make gaskets fail.  It's a 10 year old truck that's gone through it all.  Somewhere there's an air leak and/or a poor electrical connection and/or a failing sensor, and/or a failing/dirty fuel injector, that either alone or together are causing the problem.

 

Perhaps start with methodically going through the diagnosis tables in the full-service manual from GM for your vehicle...

Posted

OK UPDATE check the harness and plug that goes to the transmission if its broke or damaged in anyway replace it also look at the back of the plug for pins that may be backed out even just a little bit it will cause all kinds of stupid problems the rubber that keeps moisture from entering and keeps the pins held in should be seated all the way in the hole none of the rubber should be sticking out it should be flush or inset in its hole 

Posted
1 hour ago, lnb said:

OK UPDATE check the harness and plug that goes to the transmission if its broke or damaged in anyway replace it also look at the back of the plug for pins that may be backed out even just a little bit it will cause all kinds of stupid problems the rubber that keeps moisture from entering and keeps the pins held in should be seated all the way in the hole none of the rubber should be sticking out it should be flush or inset in its hole 

Did this fix your issue? That could make sense, the transmission was rebuilt and it did not start up for a while after. The plug may not have been fully seated and backed off a tad causing intermittent connection issues. 

  • 3 months later...
Posted

It’s been a while but tomorrow morning I am going to attempt to look at it again. Im going to see if I can do a crank position relearn as I don’t believe I did it when I changed the crank sensor. Also im going to pull Both upstream 02 sensors and swap sides to see if my problem moves to the other side. I have the truck listed for sale but no interest due to the misfire. It also has a bad steering angle sensor I may replace before it sells as well to get rid of all the lights. 

  • 3 weeks later...
Posted

Please continue working on this.  I have same problem and just as lost as you are.

Posted

I don’t believe the 02 sensor is my issue but I’m going to try and swap the 2 up stream sensors and see if the issue moves. That will atleast point me in a better direction. I’ve had various people look at the truck but they don’t want to buy it with the misfire. It’s driving me crazy and I want to get it sold. 

Posted

The voltage generated from the O2 sensor should be from 0.1V to 0.9V, with 0.9V on the rich side and 0.1V on the lean side. If your readings are within this range, the O2 sensor is functioning properly.  If you are using an OBD reader it should show what that voltage is as well as the percentage the computer is enriching or leaning the mixture.

Posted

I am going to swap the sensors over and see if the issue moves with it. I put a Bosch sensor in it at first and messed the threads up. Then I replaced the bung and removed cats and installed an Amazon sensor. I have to find a tap to clean the threads in the Bosch sensor. It’s brand new maybe was in for a week but the threads are full of metal. 

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