What this code means
P0087 may mean the control module is seeing fuel rail pressure lower than the target pressure it expects in the direct-injection system.
What the vehicle may do
- The vehicle may hesitate or feel low on power.
- The engine can run rough, stumble, or stall.
- A warning light may be present, and the symptom can be intermittent.
Possible fault areas
- Possible areas can include fuel supply, fuel leaks, fuel rail pressure sensing, fuel rail concerns, high-pressure pump drive wear, or high-pressure pump performance.
- Related fuel pressure sensor, injector, ignition, air-fuel variation, or high-pressure pump codes may affect the diagnostic direction.
Diagnostic path
What P0087 is telling you
On this Civic, P0087 means the PCM is seeing direct-injection fuel rail pressure lower than the target it expects. The vehicle may hesitate, feel low on power, run rough, stumble, stall, or turn on a warning light, depending on when the pressure falls off. Before getting deep into testing, make sure you’re following a basic, structured troubleshooting approach for this system. Then handle the basics: if the vehicle ran out of fuel and stalled before the code set, refuel it and clear the code with the HDS. If there is any fuel leak, repair that before continuing. And if other fuel pressure sensor, injector, ignition, air-fuel variation, or high-pressure pump codes are present, check what they mean first, because they can change the path for P0087.
Duplicate the low-pressure fault first
Start by trying to duplicate the failure. Start the engine, then hold engine speed at 3,000 rpm with no load — CVT in P or N, or manual transmission in neutral — until the radiator fan comes on. Then let the engine idle. Run the HDS DI fuel pressure test. If that test result is not OK, the low fuel rail pressure failure has been duplicated. If you need to match the captured conditions instead, test-drive the vehicle for several minutes in the same range as the saved snapshot data, using engine speed, vehicle speed, MAP, throttle, accelerator pedal, coolant temperature, intake air temperature, converted fuel pressure, and direct-injection fuel pressure as your guide.
Compare converted fuel pressure to direct-injection pressure
Next, inspect the fuel rail pressure sensor signal against the direct-injection pressure value. Start the engine again, hold it at 3,000 rpm with no load until the radiator fan comes on, and let it idle. For a CVT, shift to D while pressing the brake pedal firmly, then press the accelerator pedal. For a manual transmission, snap the throttle several times. On the CVT check, do not shift the transmission or lift off the brake while raising engine speed. Now compare HDS Fuel Pressure Converted From PF Sensor to Fuel Pressure Direct Injection System. Under a normal condition, those two values are almost the same. If that comparison is abnormal, treat it as a fuel rail problem.
Check the pressure reading with pressure bled down
The second fuel rail pressure sensor check starts with PGM-FI main relay 2 disconnected. Start the engine and let it idle until it stalls. After it stalls, crank the engine several times. Then confirm HDS Fuel Pressure Converted From PF Sensor. Normal is less than 1,000 kPa, and a reading of several hundred kPa is still considered normal. If this check is abnormal, the fault again points to a problem with the fuel rail.
Inspect the high-pressure pump cam drive
If the fuel rail checks do not identify the issue, move to the high-pressure fuel pump cam on the camshaft. Check it for damage or wear. A normal result means there is no damage and camshaft wear is within the specified value. If that inspection is abnormal, the problem is with the camshaft. When you find a problem there, also check the roller on the lifter attached to the high-pressure fuel pump for damage, deformation, or wear.
Last remaining item in this path
If the other inspection items are normal, the remaining high-pressure fuel pump is determined to be the cause in this diagnostic path. The key is not to jump there first. Duplicate the pressure fault, compare the two fuel pressure values, check the pressure reading after the stall-and-crank step, and inspect the pump cam drive before making that call.
Close
The takeaway for P0087 is simple: this is a commanded-versus-actual fuel pressure problem, so prove when the pressure falls short, then separate a fuel rail signal issue from a pump drive or pump issue in order. After the fault is addressed, use the same confirmation approach to verify the low-pressure condition is no longer duplicated. For more diagnostic training, visit stepdiagnostics.com.
Final check
P0087 is often best approached as a commanded-versus-actual fuel pressure fault: confirm the low-pressure condition, then follow the pressure comparison and mechanical inspection path before calling a
For more guided automotive diagnostics, visit STEP Diagnostics.
