P2028EVAP Fuel Vapor Temperature Sensor Circuit Intermittent
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P2028 covers a vapor temperature signal that jumps or briefly drops out instead of changing smoothly, as vapor temperature normally does. Public manufacturer documentation for it is lacking: Ford's 2014 list ends with P2027, and the Audi bulletins concern P2024–P2026 only. The nearest documented case is Audi's sensor inside leak detection unit J909, mounted at the canister near the rear wheel arch where water and road salt reach the connector. CARB requires input components used by the EVAP monitor to be checked for circuit faults, which leaves room for a separate intermittent code. Suspects are a loose or corroded plug, a wire chafing on the body or tank straps, or moisture inside the leak detection unit. The lamp may come and go between trips.
- What you may notice
- Warning lamp that switches on and off
- EVAP readiness slow to complete
- Likely causes
- LikelyCorroded or loose connector at the canister area
- PossibleWire chafing against body or tank straps
- RareMoisture inside the leak detection unit with integrated sensor
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €20 – €400
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.