Chevrolet Cobalt owners have reported 2 problems related to engine knocking noise (under the engine and engine cooling category). The most recently reported issues are listed below. Also please check out the statistics and reliability analysis of Chevrolet Cobalt based on all problems reported for the Cobalt.
The contact owns a 2007 Chevrolet Cobalt. The contact stated that while driving approximately 27 mph, there was a loud knocking noise heard from the engine. The contact shut the vehicle off but was unable to restart the engine. The vehicle was towed to an independent mechanic, who diagnosed that the vales in the motor were bent. The manufacturer was notified of the problem. The approximate failure mileage was 140,000.
See
all problems of the 2007 Chevrolet Cobalt
🔎.
Knocking noise from rear of vehicle from cold start. Has occurred numerous times.