P2A0FFuel Supply Heater Performance
- Generic OBD-II code · Powertrain
- How the car detects it
- A fuel supply heater warms the fuel on its way to the engine. On diesels it sits at the filter so that paraffin wax cannot block it in frost; on flex-fuel engines running on high ethanol blends heated fuel eases cold starts, as a Kia patent with a heated ethanol path to a separate cold-start injector shows. P2A0F says the heater is being driven but does not achieve the expected effect, for example the fuel temperature fails to rise. No manufacturer documents P2A0F publicly. GM diesels supervise only the electrical side of their fuel supply heater, through the relay driver (e.g. P2688), and treat that as a Type C fault without MIL; CARB covers such parts as comprehensive components. Possible consequences are hard cold starts, rough running or loss of power in severe cold.
- What you may notice
- Hard starting in cold weather
- Rough running or power loss in severe frost
- Fault code stored, warning light depending on manufacturer
- Likely causes
- LikelyHeating element burnt out or with too high resistance
- PossibleHeater relay, fuse or supply wiring not delivering full voltage
- RareFuel temperature sensor reports wrongly, so the heating effect seems absent
- Repair
- Medium · Often possible to do yourself.Typical cost: €80 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.