Piston Meltdown Causes Chevy Problems
This bulletin was released by Chevrolet, but the warning really applies to a multitude of vehicles. Some customers may complain of an SES light and a constant engine misfire. In some cases, they may also note a ticking/knocking noise. During diagnosis, the technician may find no compression on the misfiring cylinder(s) with 100% leakage into the crankcase. This may be the result of an aftermarket ECM calibration/components and detonation that lead to a melted piston.
Before disassembly of the engine, perform the following:
- If a lighted borescope is available, inspect the top of the related cylinder’s piston through the spark plug hole to determine if any of the pistons are melted. Inspect the dome and dome edges.
- Inspect for aftermarket components such as an exhaust, ignition, high performance controller, etc.
About the Author
Information courtesy of Mitchell 1
Information for Technical Service Bulletins comes from ProDemand, Mitchell 1's auto repair information software for domestic and import vehicles. Headquartered in San Diego, Mitchell 1 has provided quality repair information solutions to the automotive industry since 1918.
Mike Mavrigian
Motor Age Editor
Mike Mavrigian has written thousands of automotive technical magazine articles involving a variety of specialties, from engine building to wheel alignment, and has authored more than a dozen books that crisscross the automotive spectrum. Mike operates Birchwood Automotive, an Ohio shop that builds custom engines and performs vintage vehicle restorations. The shop also features a professional photo studio to document projects and to create images for articles and books.