A fault code doesn’t yet mean the unit or sensor itself is faulty: often it’s the plug and connector leading to it.
Possible causes
- The catalytic converter is burned out or clogged
- Rear O2 sensor
- Exhaust leak before the sensor
- Misfires in the past
What you can do yourself
- The car pulls as usual — you can keep driving.
- Weak pull and the engine “chokes” uphill — the catalyst is clogged, see a mechanic right away.
Find the part on Kaspi ShopBefore buying, check the part number or match the part by VIN in the Kaspi “Garage”.
Check how the second O2 sensor works on the “Sensors” tab.
OCases from Oleg’s practice
- Range Rover 2014 On-site diagnostics, 211.000 km: stored fan control codes (P0480, P0483, P0528), oxygen sensor codes and P0420. After clearing, all modules were “green” — we advised driving for a few days and checking again: the codes that come back will show what really needs fixing. How it went ↗
- Toyota RAV4 2005 The temperature readings jump: too high one moment, dropping sharply the next; codes P0125, P0171, P0420. The coolant temperature sensor was turning in its base — it needs replacing; for P0171 and P0420 a fuel system check is recommended. How it went ↗
The explanation comes from the error code reference in the AvtoElektrik PRO app.