2010 Cadillac CTS Sedan AWD V6-3.6L Page 1124
Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle).
3. Ignition ON, observe the manifold absolute pressure (MAP) sensor parameter. The MAP sensor pressure should be within the range specified
for your altitude. Refer to Altitude Versus Barometric Pressure (See: Powertrain Management/Computers and Control
Systems/Specifications).
瀚慖f not the specified range, refer to DTC P0106 (w/LF1) (See: P Code Charts/P0106).
Note: EVAP purge enablement may cause the FT to be momentarily outside the normal range.
4. Allow the engine to reach operating temperature. With the engine running, observe the affected Long Term FT parameter with a scan tool.
The value should be between -20 % and +20 %.
瀚慖f not the specified range, inspect for the following:
P0171 or P0174
* A mass air flow (MAF) sensor signal that is skewed-If the Short Term FT parameters for both banks changes greater than 20 % when the
MAF sensor is disconnected, refer to DTC P0101 (w/LLT) (See: P Code Charts/P0101)DTC P0101 (LF1) (See: P Code Charts/P0101).
* Fuel contamination-Refer to Alcohol/Contaminants-in-Fuel Diagnosis (with Special Tool) (See: Powertrain Management/Computers
and Control Systems/Testing and Inspection/Component Tests and General Diagnostics/Alcohol/Contaminants-in-Fuel Diagnosis (with
Special Tool))Alcohol/Contaminants-in-Fuel Diagnosis (without Special Tool) (See: Powertrain Management/Computers and Control
Systems/Testing and Inspection/Component Tests and General Diagnostics/Alcohol/Contaminants-in-Fuel Diagnosis (without Special
Tool)).
* Missing, restricted, or leaking exhaust components-Refer to Symptoms - Engine Exhaust (See: Engine, Cooling and Exhaust/Exhaust
System/Testing and Inspection/Symptoms - Engine Exhaust).
* Malfunctioning fuel injectors-Refer to Fuel Injector Solenoid Coil Test (w/LLT) (See: Powertrain Management/Computers and Control
Systems/Testing and Inspection/Component Tests and General Diagnostics/Fuel Injector Solenoid Coil Test)Fuel Injector Solenoid Coil
Test (w/LF1) (See: Powertrain Management/Fuel Delivery and Air Induction/Fuel Injector/Testing and Inspection).
* Vacuum hoses for splits, kinks, and improper connections
* Insufficient fuel in the tank
* Low fuel pressure-Refer to Fuel System Diagnosis (See: Powertrain Management/Computers and Control Systems/Testing and
Inspection/Component Tests and General Diagnostics/Fuel System Diagnosis).
* Vacuum leaks at the intake manifold, the throttle body, and the injector O-rings.
* The air induction system and the air intake ducts for leaks, or for a missing air filter element
* A cracked EVAP canister
* Evaporative pipes obstructed or leaking
* The crankcase ventilation system for leaks
* A mass air flow (MAF) sensor signal that is skewed-If the Short Term FT parameters for both banks changes greater than 20 % when the
MAF sensor is disconnected, refer to DTC P0101 (w/LLT) (See: P Code Charts/P0101)DTC P0101 (LF1) (See: P Code Charts/P0101).
* Fuel contamination-Refer to Alcohol/Contaminants-in-Fuel Diagnosis (with Special Tool) (See: Powertrain Management/Computers
and Control Systems/Testing and Inspection/Component Tests and General Diagnostics/Alcohol/Contaminants-in-Fuel Diagnosis (with
Special Tool))Alcohol/Contaminants-in-Fuel Diagnosis (without Special Tool) (See: Powertrain Management/Computers and Control
Systems/Testing and Inspection/Component Tests and General Diagnostics/Alcohol/Contaminants-in-Fuel Diagnosis (without Special
Tool)).
* Missing, restricted, or leaking exhaust components-Refer to Symptoms - Engine Exhaust (See: Engine, Cooling and Exhaust/Exhaust
System/Testing and Inspection/Symptoms - Engine Exhaust).
* Malfunctioning fuel injectors-Refer to Fuel Injector Solenoid Coil Test (w/LLT) (See: Powertrain Management/Computers and Control
Systems/Testing and Inspection/Component Tests and General Diagnostics/Fuel Injector Solenoid Coil Test)Fuel Injector Solenoid Coil
Test (w/LF1) (See: Powertrain Management/Fuel Delivery and Air Induction/Fuel Injector/Testing and Inspection) ,
* The air intake duct for being collapsed or restricted
* The air filter for being dirty or restricted
* Objects blocking the throttle body
* The evaporative emissions control system for improper operation
* Excessive fuel in the crankcase-Change the oil as necessary.
5. If all conditions test normal, test the engine for a mechanical condition. Refer to Symptoms - Engine Mechanical (See: Engine, Cooling and
Exhaust/Engine/Testing and Inspection/Symptom Related Diagnostic Procedures/Symptoms - Engine Mechanical).
6. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the
conditions that you observed from the Freeze Frame/Failure Records data.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
P0174
DTC P0171, P0172, P0174, or P0175 (LF1)
Diagnostic Instructions
