The vehicle check engine light came on and a message displayed ‘Reduced acceleration. Drive with care.’ My acceleration was very slow but that was the only symptom, although I was driving speeds under 55 MPH. I took the vehicle to GM with CEL Code P078 and they replaced the high pressure fuel rail. Two days later the CEL came on again with code P228B. I was driving on the highway when the message came on and I could not accelerate the vehicle. If I tried to push the gas pedal more than halfway, I would lose both speed and power. I could not maintain my highway speed very well and could only accelerate if I slightly pressed the gas pedal. This is a serious safety concern because it may cause an accident if I am not able to maintain speed on the freeway. Additionally, this is of concern because I rely on my vehicle to pull a camper, and with this condition, I would be a ‘sitting duck’ with my family in the vehicle. GM continues to diagnosis the issue but has failed to respond in a timeline and satisfactory manner.