Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [p0440]

This indicates that a part of the EVAP control system is no longer functioning correctly. The EVAP system consists of many parts, including (but not limited to) the gas cap, fuel lines, carbon canister, purge valve, and other hoses. The (EVAP) emission control system prevents the escape of fuel vapors from a vehicle's fuel system. Fuel vapors are routed by hoses to a charcoal canister for storage.

7
votes
1answer
2k views

Erratic single fault code: P0420, P0440, P0446. Normal variance, or indicative of something deeper?

Working on diagnosing an evap/emission/fuel system problem on my Toyota 2003 Corolla. More on that in this question. On 3/2, I saw a mechanic use his handheld OBD to read a code P0420. On 3/12, ...
7
votes
3answers
2k views

2003 Toyota Corolla, 185k: erratic OBD codes, fuel smell, other symptoms

TL;DR: O2 sensor data, thermal measurements, and physical resonance tests all point to a failed Catalytic converter. Here's the back story. MIL illuminated with codes P0440, P0420, P0404. Around this ...