2019 GMC Sierra HD Duramax Fuel Rail Pressure P1089

[ahendri]

First off I apologize if this is in the wrong forum I could not find anything related to a 2019 Sierra 2500HD.

 

I wanted to reach out the the community for some help/advice. I have been having issues with my 2019 L5P Duramax specifically the fuel rail pressure performance during deceleration fuel cut-off which is P1089. I have been to two different GM dealers and neither one have been able to successfully fix this problem. They have replaced the fuel pressure sensor and connector three different times and it still keeps returning. I am looking to you guys for some guidance hopefully someone has been down this path or has some insight on what I might be able to do. I keep asking the question to the dealership what could be causing this failure? Surely I have not just gotten my hands on 3 bad fuel pressure sensors?  My truck was in last week and I just received it back on 10/20/22 and yesterday I was coming to a stop and my truck started idling horribly and the cab was shaking almost as if it was misfiring. The CEL never came on yesterday but the traction control light did come on briefly. This cleared itself up after a short drive towards my house.  I immediately called the dealer I was just at and said something is clearly still wrong. They were nearing the end of their day yesterday and I would not have made it in time for them to read any diagnostics on it yesterday but this morning the CEL came on this morning with the same P1089 code. I drove over to the dealer this morning and there was a P0300 code that was in the history which I would expect since the general description is a Engine Misfire detected. Could an injector be going out and tripping the P1089? The dealers that I have been going to say they are following GMs procedures but that is about it. I am wondering if they are heading down the wrong path with this P1089 and something else is causing the issue masking the P1089 code? I have noticed that my truck will flutter for lack of a better way of describing it when coming to a stop. It's not downshifting its more of the RPM will flutter when coming to a stop and then when stopped they will resume to about 700 and be perfectly normal. I told the dealer about this as well and they did not have anything to comment on that.