Evaporative Emission System Control Valve
The evaporative emission system control valve is malfunctioning or not responding properly.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The system that prevents fuel vapors from escaping into the atmosphere isn't working right. This could cause gas vapors to leak out, which is bad for emissions.
What the computer is actually seeing
The engine control unit (ECU) expects the evap control valve to be either fully open or fully closed at specific times during engine operation, and it detects if the valve stays in one position when it should change.
What a healthy reading looks like
The valve should have a duty cycle of 0% when closed and 100% when fully open. Resistance should be around 20-30 ohms on the solenoid.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 1Verify the fault code is present and use a scan tool to check if any other related codes are set.
- 2Inspect the wiring and connectors to the evaporative emission control valve for signs of damage or corrosion.
- 3Test the valve with a multimeter; it should have a resistance of 20-30 ohms. If not, replace the valve.
- 4Check the duty cycle of the valve using a scan tool or oscilloscope while commanding the valve open and closed. It should respond as expected (0% to 100%).
- 5Inspect the fuel vapor lines for any clogs or leaks, and ensure they are connected properly.
Common causes
- Faulty evaporative emission control valve
- Wiring issues or poor connections to the valve
- Clogged fuel vapor lines
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Yes, it's drivable but it's best to fix it soon as it can lead to increased emissions.
Will this fault code come back after I reset it?
If the underlying issue isn't fixed, it will likely return after a short time.
Why does this code sometimes pair with SPN 4415?
Both codes relate to the evaporative emission system; if there's an issue with the control valve, it can trigger multiple faults.
Working a real vehicle right now?
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