P0469 Code: Purge Flow Sensor Circuit Intermittent

What the P0469 code means

Some vehicles have a sensor that confirms the vapors from the canister are really flowing into the engine when the purge valve opens.

The sensor gets a 5 V reference and a ground from the computer and sends back a signal between roughly 0.5 and 4.5 V. The P0469 code flags intermittent dropouts, and those almost always come from a bad contact or a damaged wire.

If the signal fails, the computer cannot verify the purge and turns on the check engine light. It does not usually affect driving, but it keeps the EVAP monitor from completing.

Intermittent faults are found by reproducing them. With the engine running and the scan tool in graph mode, move the wiring harness section by section, tap the connector gently and, if needed, warm the area with a hair dryer or wet the connector with a spray bottle. The point where the reading jumps is the point of the fault.

P0469 code symptoms

• Check engine light on.
• EVAP monitor incomplete.
• Emissions monitor incomplete, so the vehicle cannot pass inspection.
• Often there are no other driving symptoms.

Likely causes of the P0469 code

1. Bad contact in the connector from loose or backed-out pins.
2. Wire broken inside its insulation from vibration.
3. Connector exposed to water on sensors mounted under the vehicle.
4. Sensor with an intermittent fault, often temperature related.

How to diagnose the P0469 code step by step

1. Read the sensor value on the scan tool and compare it with what you expect.
2. Inspect the connector for corrosion, water or loose pins.
3. Check the reference and ground with the key on (5 V, and less than 0.1 V of voltage drop on the ground).
4. Measure the signal with the connector plugged in and see whether it changes with conditions.
5. Do a wiggle test on the wiring.
6. Check continuity to the computer.
7. Command the purge with the scan tool and watch whether the signal changes.

How to fix the P0469 code

• Repair the connector or the wiring.
• Replace the sensor if the tests confirm it is bad.
• Correct the real condition if there is one (a leak or a blockage).
• Clear the codes and complete a drive cycle so the monitor runs.

Technical reference data

• 5 V reference, ground and signal.
• Approximate values only: check the manufacturer data for your engine.

Brand-specific notes

This is an uncommon code, found mostly on some older vehicles.

P0469 on Chrysler

It is typical of some older Chrysler models.

P0469 on Ford

It is typical of some older Ford models.

Frequently asked questions about P0469