Circuit/System Verification
WARNING: This page is about a different car, the 2019 GMC Savana 3500, 2019 GMC Savana 2500, 2019 Chevrolet Express 3500, and 2019 Chevrolet Express 2500. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition - On / Vehicle - In Service Mode
- Verify there are no DTCs set related to the following system/component:
- B23 Camshaft Position Sensor
- B52 Heated Oxygen Sensor
- B66 Intake Air Temperature Sensor
- B74 Manifold Absolute Pressure Sensor
- B75C Multifunction Intake Air Sensor
- Q12 Evaporative Emission Purge Solenoid Valve
- Q17 Fuel Injector
- Q38 Throttle Body
- Engine Misfire
- Fuel Trim System
- If a related DTC is set
- Go to next step: If a related DTC is not set
- Verify the following conditions do not exist:
- Air Cleaner Element - Dirty/Missing/Restricted/Visible Damage/Water intrusion
- Evaporative Emission (EVAP) Purge System - Leaking/Saturated with fuel/Stuck Open/Visible Damage
- Exhaust System - Leaking/Restricted - Refer to: Symptoms - Engine Exhaust
- Fuel - Contaminated/Poor Quality - Refer to: Alcohol/Contaminants-in-Fuel Diagnosis
- Fuel injectors which do not close completely. - Refer to: Fuel Injector Diagnosis
- Fuel pressure that is too low or too high. - Refer to: Fuel System Diagnosis (Without FPCM) , or Fuel System Diagnosis (FPCM)
- Intake Air Duct - Loose/Poor Connection/Visible Damage
- Insufficient amount of fuel in the tank.
- Positive Crankcase Ventilation System - Dirty/Poor Connection/Restricted - Refer to: Crankcase Ventilation System Inspection/Diagnosis
- Throttle Body - Blocked/Dirty/Restricted
- If a condition exists
Repair or replace as necessary.
- Go to next step: If no condition exists
- All OK.