- Connected a scan tool and found code P0101 – Mass or Volume Air Flow "A" Circuit Range/Performance. With the engine at idle, used the scan tool to monitor the live data and found the mass airflow (MAF) sensor was below specifications. Snapped the throttle while the MAF sensor was monitored on the scan tool and observed the MAF sensor did not increase to the specified range. Inspected the air inlet tube and the air intake system for air leaks, but found no obvious faults. Using a smoke machine, induced smoke into the intake system, but did not detect any smoke exiting the air intake system. Removed the MAF sensor for inspection, visually inspected the sensing element on the MAF sensor and found no faults. Inspected the MAF sensor wiring harness and the harness connector and found no visible faults. Key on, used a multi-meter to check for the presence of the reference voltage and the signal ground at the MAF sensor harness connector and found both were present. At idle, backprobed the MAF sensor signal wire at the MAF sensor harness connector started the engine and monitored the sensor signal on a lab scope. Snapped the throttle and observed the MAF sensor signal was erratic and below the specification. With the engine at idle, monitored the MAF sensor on the scan tool, wiggled the MAF sensor and the engine wiring harnesses and observed no change in the MAF sensor signal. The results of these tests verified the MAF sensor was faulty.
- Confirmed the customer's complaint and heard a humming noise coming from the front of the vehicle when road tested. Raised the vehicle on a lift, used a stethoscope to listen to the wheel bearing and wheel hub assemblies at the front of the vehicle, and found that both front wheel hub assemblies are making noise when rotated. Grasped a wheel and found radial play in the wheel hub assembly, which indicated the wheel hub assembly on both sides are defective.
- REMOVE ALL NECESSARY COMPONENTS. REMOVE AND REPLACE MASS AIR FLOW SENSOR
- REMOVE AND REPLACE FRONT RIGHT WHEEL BEARING HUB ASSEMBLY
- REMOVE AND REPLACE FRONT LEFT WHEEL BEARING HUB ASSEMBLY
HECTOR B. gave our service a 5 star review on 1/10/2022