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.
Medium severity. Can I keep driving?Avoid long trips and hard acceleration. If you smell fuel or the car stalls, do not continue.
Symptoms
- Check engine light on
- Often no noticeable change in driving
- Starting problems or hesitation with fixed pump control
Most likely causes
- Connector corroded or loose, broken wire
- Sensor faulty
- 5 V reference disturbed (shared with other sensors)
- Engine or fuel pump control module, or CAN transmission
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: medium
- It affects emissions.
What each character of P018A means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- 1: Air and fuel
- 8A: Specific fault in that system
Frequently asked questions
Can I keep driving with code P018A?
Avoid long trips and hard acceleration. If you smell fuel or the car stalls, do not continue.
What causes code P018A?
The most common causes are: connector corroded or loose, broken wire; sensor faulty; 5 V reference disturbed (shared with other sensors).
Related codes
- P018BFuel Pressure Sensor B Circuit Range/Performance
- P018CFuel Pressure Sensor B Circuit Low
- P018DFuel Pressure Sensor B Circuit High
- P018EFuel Pressure Sensor B Circuit Intermittent/Erratic
- P0190Fuel Rail Pressure Sensor A Circuit
- P008ALow Pressure Fuel System Pressure - Too Low
Sources
- law.cornell.edu: 13 CCR 1968.2
- fordservicecontent.com: OBD Operations Summary Gasoline 2020 2023
- gsi.ext.gm.com: 18OBDG04 Engine Diagnostics
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.