Generic fault code

P2408 — Fuel cap sensor/switch, circuit: malfunction

Q: What usually causes code P2408?

Faulty, aged or drifting sensor. Mechanical wear or failure, loose or misplaced mounting. The most likely causes come first. Only a check on the car confirms which one is yours.

Q: What are the symptoms of code P2408?

Usually nothing you notice while driving. Sometimes a smell of gasoline near the car. In some cases, trouble refueling. These are the usual symptoms of this kind of fault: not all of them always appear, and sometimes you notice nothing.

The control unit stores code P2408 when it detects this fault: “Fuel cap sensor/switch, circuit: malfunction”.

Indicative severity: LowFuel and air metering

Updated on October 13, 2026

Reviewed by Daniel Morales, founder of Reprorace SL, on October 13, 2026

What does code P2408 mean?

The engine measures the incoming air and meters the fuel so the mixture is right; the throttle, the accelerator pedal and the turbo are here too. A fault usually shows as higher fuel use, jerking, lack of power or hard starting.

System: P · Powertrain
Area: Fuel and air metering · Car system: Exhaust and emissions
Type: Generic (SAE J2012 / ISO 15031-6): the same meaning on every make
Indicative severity: Low. Check at the next service; usually does not affect safety or driveability.

What usually causes code P2408?

Faulty, aged or drifting sensor
Mechanical wear or failure, loose or misplaced mounting

The most likely causes come first. Only a check on the car confirms which one is yours.

What are the symptoms of code P2408?

Usually nothing you notice while driving
Sometimes a smell of gasoline near the car
In some cases, trouble refueling

These are the usual symptoms of this kind of fault: not all of them always appear, and sometimes you notice nothing.

Can I keep driving with code P2408?

Usually yes, with care. This kind of fault does not usually affect safety or how the car drives, but have it checked at the next service. If you notice anything different (jerking, noises, smells, smoke or a red warning light), stop somewhere safe and get advice.

This is guidance only: only someone who checks the car can say whether it is safe to drive.

An indicative description of the code's generic meaning. Each manufacturer may give it a different meaning, conditions or tests: always follow its service information and your workshop's advice.

What you can do yourself

For this kind of fault

Check that the fuel cap closes properly, until it clicks, and that its seal is not damaged. Afterwards the light may take a few days of driving to go out.

Read the code and keep the report: with an ECO-LITE in the OBD socket you see it on your phone or computer, with the data captured when the fault happened.
Look for anything obvious: a loose connector, a disconnected hose, a fuel cap not closed properly or a low fluid level. Do not take apart anything you do not know.
Clear the code only after writing it down or after the repair. Clearing turns the light off, but it also deletes the freeze-frame data and the readiness monitors used at the inspection.
Drive normally for a few days and read the codes again. If the code comes back, the fault is still there: book the workshop and bring the report.

Read your car's fault codes on your phone

With an ECO-LITE in the OBD socket you see the codes in your account, with the data captured when the fault happened, and your workshop can check them remotely, always with your permission.

See the ECO-LITE Reserve (presale)

Related codes

P2405EVAP system leak detection pump, sense circuit: signal low
P2406EVAP system leak detection pump, sense circuit: signal high
P2407EVAP system leak detection pump, sense circuit: intermittent/erratic
P2409Fuel cap sensor/switch, circuit: range/performance
P2410Fuel cap sensor/switch, circuit: signal low
P2411Fuel cap sensor/switch, circuit: signal high

P24xx codes: EGR and particulate filter

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