Upstream Bank 2 sensor switching too slowly — mirror of P0133.
SYMPTOMS
- Check-engine light
- Economy loss
- Sluggish response
LIKELY CAUSES
- Aged O2 sensor
- Contamination
- Exhaust leak
DIAGNOSIS STEPS
- Compare sensor response rate in live data
- Inspect for leaks
- Replace sensor
RELATED PARTS
- Upstream O2 sensor (Bank 2)