GM is conducting a couple of service campaigns on select 2014 Chevy Sparks for noisy engines and broken transmission mounts.
The first service campaign addresses a potential knocks, ticks, and rattles coming from the engine, as well as sluggish performance. The cause has been narrowed down to a possible imperfection with the machining of the piston's ring lands. These are the grooves that the piston rings fit into. When they're too sloppy, a noise ensues that the vehicle's knock sensor picks up as pre-ignition, also referred to as engine knock or ping.
When the knock sensor senses this "noise", the performance computer retards the ignition timing, hence the sluggish and poor performance.
If engine noise is evident, dealers will test the vehicle for the relevant piston issue. If validated, dealers will replace the pistons at no charge.
The second service campaign addresses transmission mounts that are subject to breaking while driving. Should this happen, the powertrain would drop causing misalignment, possible noise, and drivetrain vibration.Dealers will inspect the transmission mounts for a specific lot number. If the mount is included in this action, it will be replaced at no charge.
Both of these actions are covered under the provisions of the Spark's new-car warranty. Work must be completed by an authorized Chevrolet dealership.
For more info or answers to questions, call Chevrolet Customer Service at 800-222-1020 or contact the NHTSA at 888-327-4236. Reference Service Campaign Number: 14076 entitled: Campaign - Engine Piston Replacement for noisy engines, and Service Campaign Number:13449A entitled: Campaign - Broken Transmission Mount for broken transmission mounts.
Hear Tom's nightly radio show, America's Car Show After Dark, Mon - Fri 8P - 10P EST on TuneIn. Call Tom during the show with your car questions at 1-866-253-2277, send your car questions to him @ firstname.lastname@example.org.