- VEHICLE SERVICE: – CHANGE ENGINE OIL AND FILTER – TIRE INFLATION CHECK – BRAKE COMPONENT INSPECTION – ALL FLUID LEVEL CHECK – RESET MAINTENCE COUNTER
- Connected a scan tool and found code P0171 – System Too Lean (Bank 1). At idle, used the scan tool to monitor live data and found the mass airflow sensor signal parameter was erratic. Inspected the air intake system and found no obvious faults. Performed a visual inspection of the mass airflow sensor and found no obvious faults. At idle, backprobed the mass airflow sensor and monitored the sensor signal on a lab scope. The mass airflow sensor signal observed on the lab scope was erratic. With the key on, engine off, used a multi-meter to check for the presence of voltage and ground at the mass airflow sensor and found both were present. Removed the mass airflow sensor and upon visual inspection found no signs of debris on the sensing element. These test results verified the mass airflow sensor was faulty. Inspected the throttle body and found the throttle body was coated in debris.
- REMOVE ALL NECESSARY COMPONENTS. REMOVE AND REPLACE MASS AIR FLOW SENSOR. REMOVE AND CLEAN THROTTLE BODY. ASSEMBLE TOGETHER AND MAKE ALL NECESSARY ADJUSTMENTS.
GUY F. gave our service a 5 star review on 8/30/2022