2004 Chevrolet Astro
Mileage
137,510
Service Date
5/14/2022
Services Performed
- Connected a scan tool and found codes: P0155 – O2 Sensor Heater Circuit (Bank 2 Sensor 1). Started the engine, increased the engine speed to 2,000 RPM while the scan tool was used to monitor the live data and found the oxygen sensor (B2-S1) was slow to respond. Performed a visual inspection of the fuses and relays, and found no obvious faults. Inspected the oxygen sensor (B2-S1) wiring harness and found no evidence of any damage. Disconnected the oxygen sensor (B2-S1) harness connector, inspected the harness connector and the terminals and found no obvious faults. Key on, used a multi-meter to check for the presence of battery voltage and ground at the oxygen sensor (B2-S1) harness connector and found both were present. Used the multi-meter to measure the resistance of the oxygen sensor (B2-S1) heater element at the oxygen sensor (B2-S1) connector and found the measured resistance was not within the specifications. The results of these tests verified the oxygen sensor (B2-S1) was faulty. Used the scan tool to monitor the live data with the engine at idle and found the mass airflow sensor parameter was below the specified range of 6-12 grams per second. Inspected the mass airflow sensor wiring harness and connector, but found no concerns. With the key on, engine off, used a multi-meter to check for the specified 12 volts and ground at the mass airflow sensor connector and found both were present. Removed the mass airflow sensor for inspection and found the mass airflow sensor was contaminated with debris. Inspected the fuel system and found no concerns. Connected a smoke machine to the air intake system, induced smoke into the system to check for leaks and found no smoke leaked. Performed a visual inspection of the throttle body and found excessive carbon buildup in the throttle body. Also recommend doing a fuel injector cleaning.
- REMOVE ALL NECESSARY COMPONENTS. REMOVE AND REPLACE OXYGEN SENSOR. ASSEMBLE TOGETHER AND MAKE ALL NECESSARY ADJUSTMENTS.
- REMOVE ALL NECESSARY COMPONENTS. REMOVE AND CLEAN THROTTLE BODY AND MASS AIR FLOW SENSOR. ASSEMBLE TOGETHER AND MAKE ALL NECESSARY ADJUSTMENTS.
- FUEL INJECTOR SYSTEM CLEANING. ADD FUEL INJECTOR CLEANER/ADDITIVE TO FUEL SYSTEM [MEANT TO RESTORE ENGINE POWER AND ACCELERATION. REDUCE IDLE AS WELL AS ELIMINATE KNOCKING]
- CERTIFICATE AND TRANSMISSION FEE
JANETTE T. gave our service a 5 star review on 5/19/2022
