17650 - Customer Advisory Letter. If this condition affects your vehicle you may noticed the CNG odor or hear a hissing sound.
To check for this condition, please have a certified CNG technician inspect the manual shut-off valve in accordance with GM Service Information procedures for CNG leakage and damage. This inspection should be performed regularly as part of the updated maintenance schedule. If the inspection is performed at a GM dealership, and your vehicle is still covered under its 5 year/50,000 mile (80,000 km) Emissions Control Systems Warranty, replacement of the manual shut-off valve, if required, will be performed for you at no charge. Additionally, we are updating the maintenance schedule in the CNG supplement to your owner manual to include regular inspection of the CNG manual shut-off valve. The insert is an amendment to your supplement. Please keep this insert with your important vehicle documents for reference.