P0193Fuel Rail Pressure Sensor A Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- The rail pressure sensor A measures the pressure in the high-pressure fuel rail of common-rail diesels and petrol direct-injection engines; it is either a three-wire sensor (5 V reference, ground, signal rising with pressure, about 0.5 V at 0 bar) or a digital SENT sensor with two measuring channels. The engine module uses it as the feedback signal for rail pressure control. P0193 means the signal is above its valid range – typically an open sensor ground or a short to voltage; where the module uses a pull-up on the signal line (Saab/GM 2.0 diesel), an open signal wire also reads 5 V and sets P0193. Limits: Ford diesel above 3.17 V (its sensor stays well below that even at maximum pressure), Ford petrol direct injection above 4.80 V for 5 s, GM above about 95 % of supply, Saab above 4.7 V. Genuine overpressure is P0088 instead. On a fault the module uses a substitute value and usually limits power.
- What you may notice
- Check engine light on
- Limp mode or 'Reduced Engine Power'
- Hard starting, stalling
- Likely causes
- LikelySensor ground open or high-resistance
- PossibleSignal wire open (with pull-up) or shorted to voltage
- PossibleConnector corroded
- PossibleSensor faulty
- RareEngine control module
- 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 – €500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.