Emission controls · Powertrain · generic (SAE-defined)
P0497: Evaporative Emission System Low Purge Flow
P0497 means the engine computer commanded evaporative emission (EVAP) purge flow but detected little or no flow from the canister into the engine.
Standard title per SAE J2012 / ISO 15031-6 · Updated 2026-11-07 · By CarWhere Research
How P0497 sets
When the powertrain control module (PCM) opens the purge valve, it expects a measurable drop in fuel tank pressure or a change in fuel trims. If those changes do not occur, the PCM concludes that purge flow is too low and sets P0497. Monitoring details vary by manufacturer.
Common causes of P0497
Roughly most likely first; the actual cause depends on the vehicle and needs testing to confirm.
- Purge valve stuck closed
- Blocked or kinked purge hose
- Restricted charcoal canister
- Open circuit in the purge valve wiring
- Faulty fuel tank pressure sensor
P0497 symptoms
- Check engine light on
- Possible fuel smell
- Possible slow refueling
- Usually no drivability symptoms
How P0497 is diagnosed
- Check for related EVAP circuit codes
- Inspect purge hoses for kinks, blockages, or disconnections
- Command the purge valve open and verify vacuum reaches the canister side
- Test the purge valve for opening when energized
- Check the canister for restriction
- Verify the tank pressure sensor responds during purge
Typical fixes for P0497
- Replace the purge valve
- Clear or replace blocked purge hoses
- Replace a restricted canister
- Repair wiring faults
Replace parts only after testing confirms the cause — a code names the circuit or condition that failed a check, not necessarily the faulty part. We don’t publish per-repair prices; for what households actually spend on upkeep, see car repair costs.
Manufacturer notes
Definitions can vary by manufacturer; check factory service information. Commonly reported on some GM vehicles.
Related codes & warning lights
P0497 FAQ
What does code P0497 mean?
P0497 means the engine computer commanded evaporative emission (EVAP) purge flow but detected little or no flow from the canister into the engine. The standard definition is "Evaporative Emission System Low Purge Flow."
Can I drive with a P0497 code?
Yes, in most cases. The engine usually runs normally, though you might notice a fuel odor and difficulty refueling if the canister becomes saturated.
What is the opposite of P0497?
P0496, which indicates purge flow is too high or present when it should not be.
Can P0497 cause the canister to fail?
If vapor is not being purged, the canister can stay saturated, which may lead to fuel odors and refueling issues over time.
Keep researching
More emission controls codes
Sources
- SAE J2012 — Diagnostic Trouble Code Definitions (standard code titles)
- ISO 15031-6 — Road vehicles: communication between vehicle and external equipment for emissions-related diagnostics, Part 6: Diagnostic trouble code definitions
- U.S. EPA — Vehicle Emissions Inspection and Maintenance (I/M) programs
- U.S. EPA, 40 CFR 86.1806-17 — Federal onboard diagnostics requirements for light-duty vehicles
- California Air Resources Board — On-Board Diagnostic (OBD) Program
General information written by CarWhere Research, not a diagnosis of your vehicle. Manufacturers can add their own sub-definitions and test conditions; confirm with the factory service information for your year, make and model. Before paying for a repair, check NHTSA for open recalls and your warranty booklet: federal law requires an emissions warranty on major emission-control parts such as the catalytic converter and engine computer.