NHTSA Complaint #11568474 — 2021 CHEVROLET SILVERADO 1500

"Cylinder 4 misfire" was the diagnostic code - the vehicle is currently at Millennium Chevrolet in Hempstead, NY. First attempt at a fix was the fuel injector - second fix is replacing the rocker arm. Emissions is still showing as an error. I was traveling to the dealership for repairs when the misfire became so bad that multiple alerts illuminated on the dash. I was in stop and go traffic at the time going 30 mph. Thankfully I was near a place to pull over out of the flow of traffic. I tow with my vehicle and just returned from a cross country trip - if this happened while towing up a grade in the western half of the country, I don't know what I would have done. Yes, the dealership confirmed the problem and it is under the powertrain warranty. I do not know if GM Engineers have inspected the engine, however, it has been in the care of a GM dealership and service center since [XXX]. [XXX] the check engine light illuminated for the first time, yet went off after .2 of a mile when I turned around to return home. I made an appointment with service at the dealership the next morning ([XXX]) and was on my way there when I no longer felt safe driving it and called for a tow truck. [XXX] - check engine came on and went off. [XXX] - check engine came on again. [XXX] - check engine - on the way to the dealership - service parking break, anti-traction control. This is when I pulled over because the vibration from the misfire of the engine became much worse. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)