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Home >> Honda >> 2014 >> Accord Plug-In >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System & Engine Mechanical - Service, Testing & Troubleshooting (Hybrid) >> Inspection/Adjustment >> Engine Compression Inspection >> Inspection
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Engine Compression Inspection: Inspection

NOTE: After this inspection, you must reset the PCM. Otherwise, the PCM will continue to stop the injectors from operating.
  1. Engine - Warm Up
    1. Enter the maintenance mode, then start the engine . Hold the engine speed at 3, 000 RPM with no load (P or N) until the radiator fan comes on, then let it idle.
  2. HDS DLC - Connect
    NOTE: For specific operations, refer to the user's manual that came with the HDS. Make sure the HDS is loaded with the latest software.

    1. Turn the vehicle to the OFF (LOCK) mode.

    2. Connect the HDS to the DLC - Refer to: How to Troubleshoot the Fuel and Emissions Systems (2014 2015), or How to Troubleshoot the Gear Unit Control System, or How to Troubleshoot the Fuel and Emissions Systems (2017)

    3. Turn the vehicle to the ON mode.

    4. Make sure the HDS communicates with the vehicle. If it does not communicate, go to the DLC circuit troubleshooting - Refer to: DLC Circuit Troubleshooting(PGM-FI System) (2014 2015), or DLC Circuit Troubleshooting(PGM-FI System) (2017)

    .
  3. Ignition Coil and Spark Plug - Remove
  4. Engine Compression - Inspect
    GHH259376Courtesy of HONDA, U.S.A., INC.
    		 1. Attach a compression gauge to the spark plug hole.

    2. Step on the accelerator pedal to open the throttle fully, then select ALL INJECTORS STOP in the PGM-FI INSPECTION menu with the HDS, and measure the compression.

    • The engine will be driven by the motor when ALL INJECTORS STOP is selected with HDS.
    • When measuring the pressure of other cylinders, make sure to stop ALL INJECTORS STOP first and replace the compression gauge and select ALL INJECTORS STOP again.

    3. Measure the compression on the remaining cylinders.

    4. If the compression is not within specifications, perform a cylinder leak down test to determine the problem area. Then check the following items, and remeasure the compression:

    • Incorrect valve clearance
    • Confirmation of camshaft timing
    • Damaged or worn cam lobes
    • Damaged or worn valves and seats
    • Damaged cylinder head gasket
    • Damaged or worn piston rings
    • Damaged or worn piston and cylinder bore

    5. Remove the compression gauge from the spark plug hole.
    Maximum Variation: 
    Within 200 kPa (2.04 kgf/cm 2, 29.0 psi) 
    Compression Pressure: 
    Above 880 kPa (8.97 kgf/cm 2, 127.6 psi) 
  5. All Removed Parts - Install
    1. Install the parts in the reverse order of removal.
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