Several GM vehicle models may feature two distinctively different-looking per-cylinder valve-cover-mounted ignition coils. This is due to a supplier difference and, according to GM, does not affect performance or serviceability.
This bulletin applies to 2016-2019 Chevy Corvette models equipped with a 6.2L LT1/LT4/LT5 engine. The SES lamp may be on and rich running condition DTCs P0172 and P0175 may be stored. The possible cause involves the high pressure fuel pump.
Owners of 2014-2016 Chevy Corvettes equipped with a 6.2L LT1 or LT4 engine and automatic transmission may comment about a rattle noise heard from the bell housing area. If service manual diagnosis does not isolate the noise, the culprit may be the flexplate due to distortion or cracking.
Some owners of 2006-2012 Chevy Corvette Z06 or 2009-2012 ZR1 models may comment on a rattle or tapping noise from under the hood.
This bulletin applies to 2014-2019 Chevy Corvettes equipped with a 6.2L LT1, LT4 or LT5 engine, regarding a concern of engine thermostat tick noise and/or running hot.
2011-2012 Corvette models equipped with the Z06 with Z07 and 2009-2012 Corvette ZR1 models equipped with J57 ceramic brake packages feature ceramic brake rotors that use an electronic sensor to indicate the need for brake pad replacement. The end of service life is communicated to the driver on the DIC (driver information center) with the message “CHANGE BRAKE PADS.”
This bulletin applies to 2009-2012 Corvette ZR1 and 2011-2012 Corvette Z06 with Z07 models, all equipped with the ceramic brake package (RPO J57).
According to GM, a “very small number” of 2013 Corvettes may exhibit an abnormal exhaust noise, due to an improperly torqued exhaust joint after the catalytic converter.
Some owners of select GM vehicles may comment on a low brake pedal during braking. See the application list at the end of this bulletin.
This bulletin applies to 2003-2014 Chevy Corvette and 2009-2014 Cadillac CTS models equipped with Magnaride (magnetically controlled suspension). The issue involves the Magnaride electrical connector not seated, along with DTCs C0575, C0580, C0585 or C0590. The customer may see a Service Suspension System message displayed on the driver’s information center (DIC).
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