NHTSA Complaint #11719615 — 2024 CHEVROLET SILVERADO 1500

After taking in to dealer for recall diagnostics and higher viscosity oil change a couple months later. Heard a noise while driving on interstate, lost cruise control, stability system, engine light came on with a ECS. Kept driving on the interstate until we got to a red light and the engine died. Cranked starter but hard to start and ran rough and died multiple times. Feathered throttle to get over 1K RPMs to get it off the street. Towed to nearest Chev dealer. P300 code. Tore engine down. Here is what dealer documented: CUSTOMER STATES CHECK ENGINE LIGHT IS ON WITH SERVICE TRACTION & SERVICE ESC MESSAGES. ENGINE IS RUNNING ROUGH AND WILL STALL. TOW IN. Valve Spring Replacement - Replacing the faulty valve spring on the cylinder 7 exhaust side is necessary as it is causing the exhaust valve to remain stuckopen, leading to engine misfire and over 80% leakage in that cylinder. This service can help restore proper engine compression and improve engine performance. Op.1 CEL -CEL: Customer states 1. replaced the exhaust valve spring and valve spring seal. reinstalled components with new seals and cleared dtcs. started engine and verified the engine starts and runs but having multiple cylinder misfires. reset engine fuel trims and brought engine to operating temperature and let it run for some time. other cylinder misfires went away but still found a dead misfire on cylinder 7. removed and swapped spark plugs with no change. noted the spark plugs have some exhaust build up on the tip due to the faulty exhaust valve spring. performed a static compression test and found the compression to be 175 psi and a running compression test with a smooth build up to 125 psi. checked spark and spark was good. tested the injector system using the AFIT test and found the test to pass indicating no faults with the fuel injectors. performed a cylinder leak down test and found no cylinder leakage coming from cylinder 7. put engine back together and cleared dtcs. reset the throttle