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DTC P0087: Fuel System Pressure Too Low
 
 
 
 
CIRCUIT OPERATION
Refer to DTC P0192 - Fuel Pressure Circuit Low Input , DTC P0628 - Fuel Pump (high pressure) Control Circuit Low .
 
 
TECHNICAL DESCRIPTION
  • The ECM monitors the signals input from the fuel rail pressure sensor.
  • Based on the input signals, the ECM checks whether the fuel rail pressure drops the minimum pressure of the system.
 
 
MONITOR EXECUTION
  • Continuous
 
 
MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)
Other Monitor (There is no temporary DTC set in memory for the item monitored below)
  • Fuel pump (high pressure) monitor
Sensor (The sensor below is determined to be normal)
  • Fuel rail pressure sensor
 
 
DTC SET CONDITIONS
Logic Flow Chart
 
 
Check Conditions
  • More than 3 seconds have passed since the engine starting sequence was completed.
  • Battery positive voltage is higher than 10 volts.
  • The estimated fuel rail pressure subtracted from the fuel rail pressure sensor output equals lower than 0 kPa (0 in.Hg).
Judgment Criteria
  • The fuel rail pressure is lower than the specified value for 15 seconds.
or
  • For 3 seconds, the estimated fuel rail pressure subtracted from the fuel rail pressure sensor output equals lower than the specified value.
 
 
FAIL-SAFE AND BACKUP FUNCTION
  • While prohibiting the operation of the injector (high pressure), carry out the control by the injector operation only.
  • Torque is restricted.
 
 
OBD-II DRIVE CYCLE PATTERN
  • Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 2 .
 
 
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
  • Fuel rail pressure sensor circuit harness damage, or connector damage.
  • Fuel pump (high pressure) circuit harness damage, or connector damage.
  • Fuel rail pressure sensor failed.
  • Fuel line failed.
  • Fuel pump failed.
  • Fuel pump (high pressure) failed.
  • Injector (high pressure) failed.
  • High-pressure fuel line failed.
  • ECM failed.
  • Run out of fuel

 
 
DIAGNOSIS
STEP 1. Check the fuel level.
Is there any fuel left?
Go to Step 2.
Refill the fuel. Then go to Step 12.
 
STEP 2. Check high-pressure fuel line and fuel line.
  • By a visual inspection and odor inspection, check around the high-pressure fuel line from the fuel pump (high pressure) to the injector (high pressure), and around the fuel line. Ensure that there is not fuel seepage and fuel leaks.
  • Remove the spark plug and check whether you smell the fuel from the plug hole or not. If you smell fuel, check a fuel leak from the injector (high pressure).
Are there any abnormalities?
Repair it. Then go to Step 12.
Go to Step 3.
 
STEP 3. Check the fuel pressure.
Refer to Fuel Pressure Test .
Is the fuel pressure normal?
Go to Step 4.
Repair it. Then go to Step 12.
 
STEP 4. Check of harness damage in HFP5 line between fuel rail pressure sensor connector and ECM connector.
Is the harness wire in good condition?
Go to Step 5.
Repair the connector(s) or wiring harness. Then go to Step 12.
 
STEP 5. Check of harness damage in HFPS line between fuel rail pressure sensor connector and ECM connector.
Is the harness wire in good condition?
Go to Step 6.
Repair the connector(s) or wiring harness. Then go to Step 12.
 
STEP 6. Check of harness damage in HFPG line between fuel rail pressure sensor connector and ECM connector.
Is the harness wire in good condition?
Go to Step 7.
Repair the connector(s) or wiring harness. Then go to Step 12.
 
STEP 7. Check of harness damage in HFP+ line between fuel pump (high pressure) connector and ECM connector.
Is the harness wire in good condition?
Go to Step 8.
Repair the connector(s) or wiring harness. Then go to Step 12.
 
STEP 8. Check of harness damage in HFP- line between fuel pump (high pressure) connector and ECM connector.
Is the harness wire in good condition?
Go to Step 9.
Repair the connector(s) or wiring harness. Then go to Step 12.
 
STEP 9. Check fuel pump (high pressure) mounting position.
  • Ensure that the plunger of the fuel pump (high pressure) and tappet do not have abrasion and damage.
  • Check whether the pump cam of the exhaust camshaft is worn down or not.
Are there any abnormalities?
Repair it. Then go to Step 12.
Go to Step 10.
 
STEP 10. Check the trouble symptoms.
(1) Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 2 .
(2) Check the diagnostic trouble code (DTC).
Is DTC P0087 set?
Go to Step 11.
It can be assumed that this malfunction is intermittent. Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions .
 
STEP 11. Replace the fuel pump (high pressure).
(1) Replace the fuel pump (high pressure).
(2) Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 2 .
(3) Check the diagnostic trouble code (DTC).
Is DTC P0087 set?
Replace the ECM (Refer to Removal and Installation ). Then go to Step 12.
The inspection is complete.
 
STEP 12. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 2 .
(2) Check the diagnostic trouble code (DTC).
Is DTC P0087 set?
Retry the troubleshooting.
The inspection is complete.