P0468 low

EVAP Purge Flow Sensor Circuit High

The P0468 code means the vehicle's onboard diagnostic system has detected: EVAP Purge Flow Sensor Circuit High. This is a low severity code.

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Keep driving?: Yes, but fix soon
DIY difficulty: moderate
Estimated cost: $80 - $300 (parts and labor)

Try This First ($8 Fix)

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Clear the Code

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Common Symptoms

Check Engine Light on
No driveability issues
EVAP monitor does not complete
Possible minor fuel odor

Probable Causes (Ranked by Likelihood)

Open circuit in purge flow sensor wiring Very High
Failed sensor (open) High
Disconnected connector Moderate
Short to reference voltage Low

Frequently Asked Questions

What causes circuit high on the purge flow sensor?

An open wire or disconnected sensor causes the signal to float to the reference voltage, indicating no valid reading.

Can a disconnected line cause P0468?

A disconnected EVAP line would not directly cause a circuit high code, but a disconnected electrical connector would.

Is the sensor replaceable?

Yes, the purge flow sensor is a separate component in the EVAP purge line and can be replaced individually.

Mechanics Guide Step-by-step diagnosis

Step-by-Step Diagnostic Procedure

Read sensor voltage. Above maximum confirms high/open circuit.
Check connector is seated.
Test wiring continuity.
Replace sensor if open.

Sources 2

This page is built from documented references. Verify against your own service info before repair work.

SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
Cross-checked against the SAE J2012:2002 DTC table (2026-08-27)archived scan of the SAE standard — readable copy, not SAE’s current edition