P0496: Evaporative Emission System Flow During Non-Purge Condition
The ECM detects fuel vapor flow through the EVAP purge line when the purge valve is commanded 0% (closed). The purge solenoid is mechanically stuck open, allowing engine manifold vacuum to draw raw fuel vapor continuously.
Driveability & Safety Advisory
Drivable, but engine will experience extended crank (hard start) immediately after refueling at gas station.
Official Manufacturer TSB Advisories
Factory Condition: Purge solenoid plunger sticks open with charcoal debris, causing hard start after refueling and P0496.
Physical Component Location & Service Access
Purge solenoid is mounted on the top or side of the engine intake manifold.
Electrical Specifications & Live PID Benchmarks
Scan Tool Live Data Targets
Digital Multimeter (DMM) Specs
Documented Model-Specific Case Studies
Root Cause: Stuck purge valve.
Verified Fix: Replace purge valve assembly.
Technician Inspection & Testing Workflow
Unplug electrical connector and vacuum hose from purge valve with engine idling.
Place finger over purge valve intake port. If there is vacuum suction while unpowered, the valve is stuck open and defective.
Replace purge valve.
Cost Breakdown
Tools & Parts Matrix
Diagnostic Questions & Answers
Why does my car only struggle to start after I put gas in it?
A stuck-open purge valve floods the engine intake manifold with heavy fuel vapors while you are pumping gas, creating an flooded engine condition.