How to troubleshoot an EVAP vent solenoid wiring?
The wiring will look completely fine until you pull on the harness. In this video I will show you how to troubleshoot and repair this condition. For more information on this topic, I have written a “field manual” called Engine Performance Diagnostics which is available as an eBook or paper book. Want even more diagnostic training?
Are there any problems with the EVAP vent?
A common problem with these EVAP vent valves is a broken wire inside of the insulation! The wiring will look completely fine until you pull on the harness. In this video I will show you how to troubleshoot and repair this condition.
How to fix an electrical connection / EVAP purge?
Checked the wiring from the body connector and found this corrosion present. Tried cleaning the connectors with a metal pick and some soda pop. Jury is still out on if this will fix the issue. Will wait to see if the check engine light comes back on. Loading…
Why is my EVAP purge vent solenoid not working?
My EVAP purge canister vent solenoid code is coming up as a trouble code. Checked the wiring from the body connector and found this corrosion present. Tried cleaning the connectors with a metal pick and some soda pop. Jury is still out on if this will fix the issue. Will wait to see if the check engine light comes back on. Loading…
When to test the vent valve on an EVAP system?
Use this handy converter to convert the EVAP system’s design pressure to a usable vacuum for testing the vent valve. When replacing, or re-installing the vent valve after testing, it is always a good idea to inspect all associated vacuum lines for signs of damage, cracking, splitting, or other issues.
What are the components of an EVAP system?
Modern EVAP systems typically consist of the fuel tank, fuel filler cap, pressure and flow sensors, a charcoal canister, vent valve with a control solenoid, purge valve with a control solenoid, fuel and vacuum lines, fuel vapor hoses, and electrical wiring / connectors.
When does a PCM need to close the vent valve?
On almost all applications, the vent valve is normally open, and the application of a 12-volt circuit current closes the valve when the PCM needs to pressurize the EVAP system to test for leaks. Problems in the control circuit or a failure of the vent valve itself will store a trouble code and trigger the CHECK engine light.
The wiring will look completely fine until you pull on the harness. In this video I will show you how to troubleshoot and repair this condition. For more information on this topic, I have written a “field manual” called Engine Performance Diagnostics which is available as an eBook or paper book. Want even more diagnostic training?
When does the ECM lock out the EVAP function?
If the ECM attempts to activate the vent control solenoid but detects incorrect voltage feedback or incorrect vacuum or pressure feedback, it will lock out EVAP function, set a diagnostic trouble code (DTC), and illuminate the malfunction indicator lamp (MIL). DTC P0446 is defined as “Evaporative Emission (EVAP) Vent Control Circuit Malfunction.”
What is the resistance of a valve solenoid?
Most valve solenoid should measure between 30 Ω and 40 Ω, though some newer electronically-controlled valves may range between 2 Ω and 6 Ω. If resistance is as specified, 0 Ω or over 10 kΩ, replace the valve. If the valve works properly and is electrically sound, check the rest of the circuit between the ECM and the valve.
What should the resistance of a vent control valve be?
Electrical Check – Check for resistance at the vent control valve. Most valve solenoid should measure between 30 Ω and 40 Ω, though some newer electronically-controlled valves may range between 2 Ω and 6 Ω. If resistance is as specified, 0 Ω or over 10 kΩ, replace the valve.