this has to gdt to the dealer or a shop that works on these Duramax engines
it needs to be towed to a shop i am sorry to say
below is what i think you have going on here
7.Ignoring the message and continuing to drive with the warning message ON and the exhaust filter not being cleaned as required will eventually result in the following:
7.1.The malfunction indicator lamp (MIL) will illuminate at which point the DPF warning message will be displayed and a chime will also sound.
7.2.Diagnostic Trouble Code DTC P2463 will be set as a result of excessive soot loading in the DPF.
7.3.The Engine Power Is Reduced message will be displayed. The engine WILL operate in reduced engine power when this occurs.
7.4.Once this occurs, self cleaning of the DPF is no longer possible and dealer service will be necessary.
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