P013E O2 Sensor Delayed Response - Rich to Lean Bank 1 Sensor 2
The downstream oxygen sensor (sensor 2, after the catalytic converter) is used for fine mixture trim and to monitor the converter. 'Delayed response' means the sensor starts reacting too late, or does not reach the target level at all, after the mixture has changed. This code covers the rich-to-lean direction, usually tested during deceleration fuel cut-off. GM checks whether the signal falls below 450 mV before about 45 g of air have passed after the forced change; failing needs two trips. Ford counts it as stuck in range if the sensor does not drop below 0.1 V within 5–10 s of fuel cut-off. Bulletins often point elsewhere: Audi fixed P013E with software and said not to replace the sensor, VW names exhaust leaks or the converter. CARB requires separate detection of slow and delayed faults in each direction (phased in from 2009 for downstream and 2011 for upstream sensors).
Likely causes
Symptoms
- Check engine light on
- Usually no noticeable change in driving
- Catalyst monitor may stay incomplete (inspection readiness missing)
- With a converter cause, P0420/P0430 may follow
Repair estimate
Typical range across vehicles; the real cost depends on what the testing finds.
Parts involved
Related codes
References: law.cornell.edu, gsi.ext.gm.com, newtonnet.co.uk, static.nhtsa.gov.