Toyota Sienna 2010 LE AWD - P0138 O2 Sensor Error After Under-Hood Detailing
Hi everyone, I own a 2010 Toyota Sienna LE AWD. Shortly after a recent under-the-hood detailing session — which included cleaning the engine bay and leaving residual moisture in various areas — my check-engine light came on with code P0138, along with the VSC warning light. The vehicle drives normally without any performance issues. The detail technician mentioned that occasional water exposure during cleaning can trigger temporary error codes, suggesting they might resolve within 24 hours. However, I'm wondering if this is a real issue or just a transient fault. Could P0138 be caused by moisture affecting the oxygen sensor or engine control module? Should I attempt to clear the code myself, or does it indicate actual damage to the O2 sensor? Any insights on whether under-hood washing or cleaning can trigger such codes in Toyota Sienna 2010 models? Thanks! -- dz108
Quick update: I also found a P0606 code. Since these types of error codes often appear when there's an underlying issue, I decided to reset them. I ran the vehicle for several hours and performed multiple restarts — the check-engine light has not returned since. I'll monitor it again tomorrow. If no further issues arise, I’ll assume the codes were temporary. Does anyone have any thoughts on how under-the-hood detailing or washing might affect O2 sensor readings or engine control system diagnostics? Thanks!