Code result

P04F0

EVAP System High Load Purge Line A Performance

Moderate severity

What it means

On engines that have a separate high-load purge line - to use boost pressure to pull vapor on turbo applications - the ECU monitors flow when this path is commanded. The flow is below the expected level - the venturi, line, or check valve is restricted, or the line is incorrectly routed.

Is it safe to drive?

Use caution

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.

Most likely causes

  • Line, venturi or check valve restricted

    high

    One of the most commonly reported causes for this code — check this first.

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