So I had my 2023 GMC Sierra 3.0 Duramax (25,000 current miles) at the dealership for an under warranty DEF tank problem. They ordered a DEF tank assembly for me and it should arrive in about 6 weeks. Anyway I picked it up and drove it a mile or so and saw the check engine light was on. Did a U turn and brought it back to the dealership for them to look at. They said the check engine light was on because 2 modules were not talking to each other and they have never seen that before. Cleared the code and said I should be good to go.
Then Onstar sent me an email stating it was a P00C7 code and gave me this:
The Engine and Transmission System is not performing as expected. An issue has been detected in the Air Induction System which monitors and controls air intake to the engine. If the check engine light is flashing, a misfire condition has been detected. A misfire increases vehicle emissions and could damage the emission control system on the vehicle. Please reduce vehicle speed, avoid hard accelerations, avoid steep uphill grades, and reduce any cargo loads such as a trailer.
Does that sound right to you people?
Then Onstar sent me an email stating it was a P00C7 code and gave me this:
The Engine and Transmission System is not performing as expected. An issue has been detected in the Air Induction System which monitors and controls air intake to the engine. If the check engine light is flashing, a misfire condition has been detected. A misfire increases vehicle emissions and could damage the emission control system on the vehicle. Please reduce vehicle speed, avoid hard accelerations, avoid steep uphill grades, and reduce any cargo loads such as a trailer.
Does that sound right to you people?
