Circuit/System Testing

WARNING: This page is about a different car, the 2018 Chevrolet Suburban 3500 HD. However, it is still accessible from the selected car via links, so may be relevant.

Ignition ON.
Verify the MAP sensor pressure parameter is within the range specified for your altitude. Refer to Altitude Versus Barometric Pressure .
- If not within the specified range
  Refer to DTC P0106 .
- Go to next step: If within the specified range
Engine running at the operating temperature.
Verify the Long Term Fuel Trim Bank 1 or 2 parameters are between -28% and +28%.
- If greater than +28%
1. Ignition OFF.
2. Inspect for the conditions listed below:
  - Split, kinked, or improperly connected vacuum hoses
  - Insufficient fuel in the tank
  - Low fuel pressure. Refer to Fuel System Diagnosis .
  - Fuel contamination. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
  - Malfunctioning fuel injectors. Refer to Fuel Injector Diagnosis .
  - Missing, restricted, or leaking exhaust components. Refer to Symptoms - Engine Exhaust .
  - Vacuum leaks at the intake manifold, the throttle body and the injector O-rings
  - Leaks in the air induction system and the air intake ducts
  - Missing filter element
  - A cracked EVAP canister
  - Obstructed or leaking evaporative pipes
  - Leaks in the crankcase ventilation system. Refer to Crankcase Ventilation System Inspection/Diagnosis .
    - If a condition is found, repair as necessary.
    - If no condition is found, test the engine for a mechanical condition. Refer to Symptoms - Engine Mechanical .
- If less than -28%
1. Ignition OFF.
2. Inspect for the conditions listed below:
  - Collapsed or restricted air intake duct
  - Dirty or restricted air filter
  - Objects blocking the throttle body
  - Excessive fuel in the crankcase
  - Improper operation of the evaporative emissions control system
  - Excessive fuel pressure. Refer to Fuel System Diagnosis .
  - Missing, restricted or leaking exhaust components. Refer to Symptoms - Engine Exhaust .
  - Malfunctioning fuel injectors. Refer to Fuel Injector Diagnosis .
  - Fuel contamination. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
    - If a condition is found, repair as necessary.
    - If no condition is found, test the engine for a mechanical condition. Refer to Symptoms - Engine Mechanical .
- Go to next step: If between -28% and +28%
All OK.