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P0191

Fuel Rail Pressure Sensor Circuit Range/Performance Bank 1

The engine computer is not seeing a fuel pressure reading that makes sense. This can happen if the fuel pressure sensor, wiring, fuel pump, or fuel pressure regulator is failing. The engine may run poorly, hesitate, stall, or not start.

Severity4/5 High
Can I drive?⚠ With caution

You may be able to drive short distances if the engine runs normally, but the problem can cause stalling, poor power, or a no-start condition. Avoid long trips and get it checked soon.

DIY
$20–$200
Shop
$150–$600
Difficulty
intermediate

What It Means

P0191 means the powertrain control module detected fuel rail pressure sensor input that is outside the expected range or does not match commanded fuel pressure. The fault may be in the sensor signal, sensor power or ground, wiring, fuel pressure control system, or actual fuel pressure. The code is set when the reading is implausible, unstable, or inconsistent with engine operating conditions.

Symptoms

Common Causes

1. Faulty fuel rail pressure sensorhigh
2. Damaged wiring, loose connector, corrosion, or poor terminal fit at the fuel pressure sensor or fuel pressure control circuithigh
3. Low fuel pressure from weak fuel pump, clogged fuel filter, restricted pickup, or failing in-tank pump modulemedium
4. Fuel pressure regulator or fuel volume control valve problemmedium
5. Fuel rail pressure sensor circuit power, ground, or reference voltage problemmedium
6. ECM/PCM software issue or rare module faultlow

Related Codes

FAQ

Is P0191 caused by bad fuel?

Bad fuel can contribute to fuel system problems, but P0191 is usually caused by a sensor, wiring, or fuel pressure control issue.

Can P0191 make the car not start?

Yes. If fuel pressure is too low or the signal is wrong enough, the engine may crank but not start.

Will replacing the fuel pressure sensor fix P0191?

Sometimes, but only if the sensor is actually faulty. Wiring and real fuel pressure problems are also common.

Do I need to drive immediately with P0191?

No. If the engine is running poorly or stalling, it should be diagnosed before further driving.