P0087: Fuel Rail/System Pressure Too Low

What is P0087?

P0087 is a diagnostic trouble code (DTC) that stands for “Fuel Rail/System Pressure Too Low” and indicates a fault within the fuel delivery system.

It is usually triggered by the Powertrain Control Module (PCM) when it detects the pressure inside the fuel rail or the fuel system to be below the minimum levels. When this happens, your car may not have the pressure needed to supply the engine with sufficient fuel to run properly.

Note: Code P0087 is a generic SAE code that may slightly differ from manufacturer to manufacturer. However, it generally indicates problems with low pressure in the fuel rail system that is affecting fuel supply.

Common symptoms

Code P0087 can manifest in several different ways, including an illuminated check engine light and engine stalling.

Let’s take a closer look at some of these:

• Check Engine Light Turns On: Since the car experiences issues with the fuel system pressure in code P0087, the Powertrain Control Module triggers the engine light to alert the driver.
• Reduced Fuel Efficiency: Low fuel pressure can often lead to insufficient fuel reaching the engine. In turn, your engine may consume more fuel than it needs, affecting the car’s fuel economy.
• Poor Vehicle Performance: Another symptom of low fuel rail pressure in your car can be reduced engine performance, including frequent stalling, rough running, running lean, high RPMs (revolutions per minute), or the car stopping altogether.
• Misfiring Engine: When the engine receives insufficient fuel supply for combustion, it will result in a faulty air fuel mixture that can cause lean misfires.

Can I still drive?

Code P0087 is a moderately serious code that can cause severe drivability issues if ignored. Most mechanics advise against driving with an active P0087 code.

If you encounter a bad fuel pump or the fuel filter becomes completely clogged, this may cause the engine to die and lead to costly repairs. So as soon as you notice these symptoms or see your engine light switch on, contact a mechanic for help.

P0087 causes

DTC P0087 can be triggered by a combination of one or more issues.

These include:

• Clogged fuel filter or fuel screens
• A weak fuel pump or a bad fuel pump 
• A faulty fuel pressure regulator sensor
• Restricted fuel line or fuel hoses, or incorrect fuel rail pressure
• Electrical problems with the low pressure fuel pump, fuel rail pressure sensor, or the high pressure pump solenoid
• A broken or worn high pressure pump
• Camshaft timing or camshaft lobe wear on the pump drive (rare)
• Faulty fuel rail pressure sensor reading incorrect fuel pressure measurements (rare)

Diagnosis

Here’s how a mechanic would diagnose DTC P0087:

1. Start by connecting the engine to an OBD-II scan tool. Check for other codes and capture freeze frame data.
2. Perform a road test and verify if the codes persist.
3. If the check engine light turns on, perform a visual inspection of the fuel tank, fuel line, and fuel filter.
4. Next, your mechanic will measure the manual fuel pressure readings at the fuel rail and compare them to specifications. They’ll then use a scan tool to compare manual readings to what the ECM sees. 
5. Lastly, they’ll inspect the fuel pump for any damage or fuel leaks. External fuel tank damage could affect the fuel propeller inside the tank, leading to poor fuel intake by the low pressure fuel pump.

Possible repairs for P0087 & Costs

Code P0087 can require a number of repairs depending on its severity and root cause.

These may include:

• Replacing the fuel filter or fuel screen
• Replacing the bad fuel pump
• Replacing the frayed, damaged, or kinked fuel lines
• Replacing the faulty fuel sensor
• Repairing or replacing the fuel tank (rare)

Repair Costs: 

Mechanics may charge anywhere from $100 to $150 for diagnosing a check engine code issue. They can then quote a relevant figure depending on the repairs needed for your car.

On average, repairing a P0087 fuel rail system pressure code can be quite expensive. It can range from $50 on the low end and go as high as $2000 in rare scenarios.

That being said, you can usually expect the following repair costs (including the cost of parts and labor charges) with a DTC P0087:

• Fuel filter replacement: $50 – $175
• Fuel line or fuel hose replacement: $120 – $500
• Fuel pressure sensor replacement: $100 – $300
• Fuel tank replacement: $900 – $2100

3 Code P0087 FAQs

Here are some common queries about the P0087 fuel railsystem pressure code and their answers.

1. How Does The Fuel System Work?

The fuel system in your car works to store and supply fuel to the engine for combustion. It consists of several components, including the combustion chamber, intake valve, fuel injector, fuel pump, fuel pressure regulator, pistons, etc.

The fuel pump draws gas from the fuel tank where it is stored for use. It then passes the fuel through the fuel lines into the fuel filter.

Once it is filtered for impurities, it reaches the fuel injector and is injected into the engine for combustion. 

2. What Is A Fuel Rail?

The fuel rail is a critical component that supplies fuel flow to the injector system. Once the high pressure pump applies system pressure to the fuel, the fuel rail delivers it to the injectors.

A fuel pressure sensor on the rail measures the actual fuel pressure as a control variable. The fuel rail pressure sensor also monitors the fuel level and alerts the ECU, which then uses it to make adjustments to the vehicle’s fuel and timing.

Note: A weak fuel pump, clogged fuel filter, or a clogged tank pump inlet strainer can sometimes result in a low fuel pressure system. This can be dangerous for the car and cause engine stalling.

3. What Is The Difference Between The High Pressure Fuel Pump And Low Pressure Fuel Pump?

Most vehicles have two fuel pumps to facilitate fuel delivery and appropriate fuel flow for combustion. 

The low fuel pressure pump siphons your gas and moves it from the gas tank to the high pressure fuel pump.

The high pressure fuel pump is a device that serves to compress fuel in order to force it through the fuel injector for combustion. Attached to it is the fuel pressure regulator that controls the pressure of the fuel supplied to the injectors.

As a result, the engine continues its duty cycle and combusts the fuel-air mixture without encountering any errors like misfires, fuel leaks, etc.