Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer thinks the fuel pressure is too high before the engine even starts.
The fuel rail pressure sensor is detecting a higher than expected pressure in the fuel rail before the engine is started on Bank 2.
The Powertrain Control Module (PCM) monitors the fuel rail pressure sensor to ensure the fuel pressure is within the expected range before the engine starts. If the pressure is detected to be too high, it triggers the P117D code. This could indicate a faulty sensor or a problem in the fuel system causing excessive pressure.
• Check Engine Light is on
• Difficulty starting the engine
• Poor fuel economy
• Faulty fuel rail pressure sensor
• Fuel pressure regulator malfunction
• Fuel pump delivering excessive pressure
PCM: Powertrain Control Module
Fuel Rail: A pipe that delivers fuel to the engine's injectors
• Use an OBD-II scanner to confirm the P117D code.
• Inspect the fuel rail pressure sensor and its wiring.
• Measure the actual fuel pressure in the rail using a mechanical gauge.
• Replace the faulty fuel rail pressure sensor.
• Repair or replace damaged wiring or connectors.
• Inspect and replace the fuel pressure regulator if necessary.
• OBD-II scanner
• Fuel pressure gauge
• Multimeter
$150 - $400
Moderate
• BMW 3 Series
• Mercedes-Benz C-Class
• Audi A4
• Regularly inspect fuel system components.
• Use high-quality fuel.
• Perform scheduled maintenance.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Avoid driving the vehicle under heavy load until repaired.
Check with your vehicle manufacturer for warranty coverage on fuel system components.
This code has been associated with issues in vehicles with direct fuel injection systems.
Moderate – It may not cause immediate harm but should be addressed to prevent potential engine performance issues.
Driving with an unresolved fuel pressure issue can lead to engine performance problems and may be unsafe.
• Engine off
• Key in the ON position
The fuel rail pressure sensor is typically located on the fuel rail, which is mounted on the engine.
Q: Can I drive with a P117D code?
A: It's not recommended to drive for long periods with this code, as it can lead to engine performance issues.
Q: How do I clear a P117D code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is fixed, the code should not return.
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