One or both secondary air injection check valves may become restricted causing poor air flow resulting in illumination of the Check Engine Light. It is often recommend to replace both check valves even if a fault code is set for only one bank of cylinders. Replacing only one valve may result in a return trip to the repair shop.
Check Engine Light Due to Restricted Secondary Air Injection Check Valve on GMC Sierra 1500 HD
Average mileage: 100,150 (100,150–100,150)
8 people reported this problem
1 person shared problem details
2001 GMC Sierra 1500 HD100,150Visitor
Illumination of the Check Engine Light can be caused by a loose or worn gas cap.
One or more heater & AC (HVAC) temperature and/or air delivery mode door actuator may fail,...
A dirty throttle body may cause a lower than normal idle and possible stalling condition. Perfo...
A rattling noise may develop from the AC belt tensioner. This can be caused by an internal faul...