P0468 code meaning
EVAP Purge Flow Sensor Circuit High
Powertrain system Generic code P04xx codes Check engine light
What P0468 means
The evaporative emission (EVAP) system stores fuel vapour from the tank in a charcoal canister; a purge valve lets the engine draw it off, and a vent valve opens the canister to fresh air. A purge flow sensor – a heated thermistor in the purge line between purge valve and intake manifold, as described in a Ford patent – measures purge flow directly for the CARB purge monitor. Today indirect methods (fuel trim, tank vacuum) have largely replaced it; no manufacturer document available to us uses these codes. P0468 means the signal voltage is above its upper limit – signal or ground open with a pull-up, or a short to positive. The purge flow monitor can then not be evaluated.
P0468 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.3 to 1.5 hours
- Clears after repairAfter a drive cycle
Symptoms of P0468
- Check engine light on
- EVAP readiness not set, emission inspection not passed
- No change in driving
Common causes of P0468
- Most likelySignal or ground wire open
- PossibleSensor faulty
- Less likelyShort to positive
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
EVAP purge flow sensorPurge lineSensor wiringEngine control module
What each part of P0468 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 4 | Area: auxiliary emission controls (catalytic converter, EGR, EVAP). |
| 68 | The exact fault in that area. |
What to do next
- Note P0468 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0468
What does P0468 mean?
P0468 means "EVAP Purge Flow Sensor Circuit High". The evaporative emission (EVAP) system stores fuel vapour from the tank in a charcoal canister; a purge valve lets the engine draw it off, and a vent valve opens the canister to fresh air. It is a generic code, so it means the same on every make.
Is it safe to drive with P0468?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P0468 fail an emissions test?
Yes, it can. P0468 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0468 to fix?
Difficulty: medium. A typical repair takes 0.3 to 1.5 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P0468 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.