Summary
P0443 means the PCM detected an electrical fault in the EVAP purge valve circuit — not a leak, but a problem with the valve's wiring, connector, or internal solenoid. The most common cause is a failed purge valve solenoid (45%), followed by wiring damage or a corroded connector (30%) and a blown fuse (15%). The purge valve is usually on top of the engine near the intake manifold — a $15–$60 part with easy access.
Severity: Low — emissions code
Safe to drive: Yes
Repair cost: $15–$200 depending on cause
DIY difficulty: Easy to Moderate
What does P0443 mean?
The EVAP purge valve controls the flow of fuel vapors from the charcoal canister to the intake manifold. The PCM opens and closes it by energizing a solenoid. P0443 sets when the PCM detects an abnormal electrical condition in the purge valve circuit — typically an open circuit (no current flow), a short to ground, or a short to voltage.
Unlike P0441 (incorrect purge flow — a performance issue), P0443 is a circuit-level fault. The PCM can't communicate properly with the purge valve, not just that purge flow is wrong.