O2 Sensor Pumping Current Trim Circuit/Open Bank 2 Sensor 1
P2629 indicates a problem with the oxygen sensor's pumping current trim circuit, affecting fuel mixture control. This moderate severity code will worsen if not addressed promptly.
What You Might Notice
- Check Engine Light illuminated
- Poor engine performance that worsens over time
- Engine running lean or rich
- Increased fuel consumption
- Smoke from tailpipe
Most Common Causes
- 1
Faulty O2 Sensor
Oxygen sensor degradation prevents proper fuel mixture adjustment.
- 2
Fuel Pressure Issue
Excessively high or low fuel pressure disrupts the trim circuit feedback.
- 3
Exhaust Leak
Excessive exhaust leakage allows outside air to reach the O2 sensor, skewing readings.
- 4
Corroded Wiring/Connector
Damaged wiring or corroded connectors interrupt sensor signal transmission.
How to Diagnose It
- 1
Check Faulty O2 Sensor — Oxygen sensor degradation prevents proper fuel mixture adjustment.
- 2
Check Fuel Pressure Issue — Excessively high or low fuel pressure disrupts the trim circuit feedback.
- 3
Check Exhaust Leak — Excessive exhaust leakage allows outside air to reach the O2 sensor, skewing readings.
- 4
Check Corroded Wiring/Connector — Damaged wiring or corroded connectors interrupt sensor signal transmission.
How to Fix It
- 1
- 2
Check Fuel Pressure
Test and adjust fuel pressure to manufacturer specifications.
- 3
Repair Exhaust Leaks
Seal or replace damaged exhaust components causing air intrusion.
- 4
Inspect Wiring and Connectors
Clean corrosion or replace damaged wiring and sensor connectors.
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