Buick Regal P0139: O2 Sensor Slow Response (Bank 1 -Sensor 2)

P0139 is a common OBDII code that occurs in many vehicles, including the Buick Regal. The code is triggered when there is an issue with the response time from the oxygen (O2) sensor when switching voltage levels. The Oxygen sensors are responsible for helping the ECM meter oxygen levels in the exhaust, and helping to … Read more

Buick Regal P0140: O2 Sensor → No Activity Detected B1S2

P0140 is a generic OBDII trouble code. It has the same meaning for any vehicle with OBDII, including the Buick Regal. It means that the PCM/ECM is not detecting any activity from the sensor.  It doesn’t mean that the O2 sensor isn’t getting power, but that the voltage isn’t changing, which is the “no activity”. … Read more

Buick Regal P0151 Code: Meaning, Causes, How to Fix

The P0151 code is an OBD-II diagnostic trouble code that indicates low voltage in the Buick Regal’s Oxygen (O2) sensor circuit located at Bank 2, Sensor 1 (B2S1). The B2S1 O2 sensor plays a crucial role in maintaining optimal engine performance by detecting the air-fuel ratio in the exhaust, then sending this data to the … Read more

Buick Regal P0134: O2 Sensor → No Activity Detected B1S1

P0134 is a relatively common OBDII trouble code. It’s generic, which means that it has the same meaning for any vehicle with OBDII. It means that the PCM/ECM is not detecting any activity from the sensor.   P0134 Definition P0134: O2 Sensor → No Activity Detected →Bank 1 Sensor 1 The Regal’s computer uses the … Read more

Buick Regal P0403:EGR→ Circuit Malfunction

P0403 is a very common trouble code. It is a generic code, which means that it has the same meaning for the Buick Regal as it would any other vehicle. It affects the EGR (Exhaust Gas Recirculation System and technically means: P0403: EGR→ Circuit Malfunction A circuit malfunction implies that there is a wiring problem … Read more

Buick Regal P0402: EGR → Excessive Flow Diagnosis

P0402 is an OBDII trouble code that’ll pop up in the Buick Regal. It has to do with the emissions system and stands for: P0402: EGR → Excessive Flow Diagnosis The EGR system on a vehicle is responsible for recirculating exhaust gasses in order to lower the vehicles emissions output. The amount of gas cycled … Read more

Buick Regal P0404: EGR Circuit → Range/Performance

With the Buick Regal, P0404 is going to have the same meaning as it would in any other vehicle. It’s a generic powertrain code that stands for: P0404: EGR Circuit → Range/Performance While there are several issues that can throw the P0404 code in the Regal, the most common issue is either going to be … Read more