P018AFuel Pressure Sensor B Circuit
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- Fuel pressure sensor B is a second fuel pressure sensor; which one is up to the manufacturer. On GM it is the low-pressure sensor in the supply line of direct-injection engines (0–743 kPa), read by the engine module or the fuel pump control module; on Ford engines with dual injection it is the sensor on the port-injection rail (0.5–4.5 V for about 0–70 psi). Sensor A is the high-pressure rail sensor (P0190–P0194). P018A is the general circuit fault for when a manufacturer does not distinguish low from high. GM and Ford, whose sensor B functions are documented, use P018C/P018D instead, so no manufacturer document using exactly this code was found; the description rests on CARB's circuit monitoring requirement and the component information. When the sensor fails, the control module uses a pre-set value and usually runs the supply pump with fixed control.
- What you may notice
- Check engine light on
- Often no noticeable change in driving
- Starting problems or hesitation with fixed pump control
- Likely causes
- LikelyConnector corroded or loose, broken wire
- PossibleSensor faulty
- Possible5 V reference disturbed (shared with other sensors)
- RareEngine or fuel pump control module, or CAN transmission
- 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: €50 – €300
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.