NO.12 LACK/LOSS OF POWER-ACCELERATION/CRUISE [SKYACTIV-G 2.5T]
id0103q4801800
12 |
LACK/LOSS OF POWER-ACCELERATION/CRUISE |
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DESCRIPTION
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• Performance is poor under load. (e.g., power down when climbing hills)
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POSSIBLE CAUSE
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• Engine overheating
• Drive-by-wire control system operates with brake override system
• PCM DTC is stored
• Erratic signal to PCM
• Improper operation of A/C system
• Improper operation of drive-by-wire control system
• Throttle body malfunction
• Incorrect fuel injection timing
• Fuel injector malfunction
• Purge solenoid valve malfunction
• Fuel leakage
• Poor fuel quality
• Air leakage or restriction in intake-air system
• Vacuum leakage
• Air cleaner restricted or dirty
• Charge air cooler malfunction
• Brake dragging
• Tire air pressure malfunction
• Erratic signal from CKP sensor
• Erratic or no signal from CMP sensor
• Inadequate fuel pressure (high or low pressure side)
• Throttle valve restricted or clogged
• Low engine compression
• Improper intake valve timing
• Improper exhaust valve timing
• Wastegate control system malfunction
• Improper operation of electric variable valve timing control system
• Improper operation of hydraulic variable valve timing control system
• Spark plug malfunction
• Ignition coil malfunction
• Exhaust system and/or TWC restriction
• PCV valve malfunction
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POSSIBLE CAUSE
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• EGR valve stuck open
• Three way solenoid valve stuck open
• Turbocharger malfunction
• Injector driver (built-into PCM) malfunction
• AT internal malfunction
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Diagnostic Procedure
STEP |
INSPECTION |
RESULTS |
ACTION |
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1
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VERIFY IF MALFUNCTION INCLUDES ROUGH IDLING
• Does the engine idle rough?
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Yes
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Perform the symptom troubleshooting “NO.8 ENGINE RUNS ROUGH/ROLLING IDLE”.
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No
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Go to the next step.
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2
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VERIFY IF MALFUNCTION CAUSE IS OVERHEATING
• Access the ECT PID using the M-MDS.
• Is the ECT PID value less than 116 °C {241 °F} during driving?
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Yes
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Go to the next step.
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No
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Perform the symptom troubleshooting “NO.17 COOLING SYSTEM CONCERNS-OVERHEATING”.
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3
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CONFIRM DRIVE-BY-WIRE CONTROL SYSTEM OPERATES WITH BRAKE OVERRIDE SYSTEM
• Retrieve the PCM DTC using the M-MDS.
• Is the DTC P2299:00 present?
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Yes
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Go to the applicable DTC inspection. (drive-by-wire control system operates with brake override system.)
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No
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Go to the next step.
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4
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VERIFY PCM DTC
• Retrieve PCM DTCs using the M-MDS.
• Are any DTCs present?
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Yes
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Go to the applicable DTC inspection.
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No
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Go to the next step.
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5
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VERIFY CURRENT INPUT SIGNAL STATUS
• Access the following PIDs using the M-MDS:
• Do the PIDs indicate the correct values under the trouble condition?
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Yes
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Go to the next step.
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No
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APP1, APP2 PIDs are not as specified:
• Inspect the APP sensor.
ECT PID is not as specified:
• Inspect the ECT sensor.
FUEL_PRES PID is not as specified:
• Inspect the high fuel pressure sensor.
IAT PID is not as specified:
• Inspect the IAT sensor No.1.
MAF PID is not as specified:
• Inspect the MAF sensor.
MAP, MAP_V PIDs are not as specified:
• Inspect the MAP sensor.
TP_REL PID is not as specified:
• Inspect the TP sensor.
O2S11, SHRTFT1, LONGFT1 PIDs are not as specified:
• Inspect the A/F sensor.
O2S12 PID is not as specified:
• Inspect the HO2S.
INLET_PRES PID is not as specified:
• Inspect the boost pressure sensor inspection.
Repair or replace the malfunctioning part according to the inspection results.
• If the malfunction remains:
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6
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INSPECT DRIVE-BY-WIRE CONTROL SYSTEM OPERATION
• Perform the Electronic Control Throttle Operation Inspection.
• Does the drive-by-wire control system work properly?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning part according to the inspection results.
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7
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INSPECT FUEL INJECTOR OPERATION
• Perform the Fuel Injector Operation Inspection.
• Do the fuel injectors operate properly?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning part according to the inspection results.
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8
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INSPECT PURGE CONTROL SYSTEM OPERATION
• Perform the Purge Control System Inspection.
• Does the purge solenoid valve work properly?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning part according to the inspection results.
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9
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INSPECT FUEL SYSTEM FOR FUEL LEAKAGE
• Inspect for fuel leakage in the fuel line.
• Is there any leakage?
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Yes
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Repair or replace the malfunctioning part according to the inspection results.
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No
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Go to the next step.
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10
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INSPECT RELATED PART CONDITION
• Inspect the following:
• Is there any malfunction?
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Yes
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Service if necessary.
• Repeat this step.
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No
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Go to the next step.
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11
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INSPECT FUEL PRESSURE (HIGH-SIDE)
• Start the engine and warm it up completely.
• Access the FUEL_PRES PID using the M-MDS at idle.
• Is the FUEL_PRES PID value approx. 3 MPa {31 kgf/cm2, 435 psi}?
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Yes
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Go to Step 13.
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No
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Lower than 3 MPa {31 kgf/cm2, 435 psi}:
• Inspect the following:
• If there is any malfunction:
• If there is no malfunction:
Higher than 3 MPa {31 kgf/cm2, 435 psi}:
• Go to the next step.
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12
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INSPECT SPILL VALVE CONTROL SOLENOID VALVE CONTROL CIRCUIT FOR SHORT TO GROUND
• Switch the ignition off.
• Disconnect the high pressure fuel pump and PCM connectors.
• Inspect for continuity between high pressure fuel pump terminal A (wiring harness-side) and body ground.
• Is there continuity?
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Yes
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Refer to the wiring diagram and verify whether or not there is a common connector between high pressure fuel pump terminal A and PCM terminal 1EE.
If there is a common connector:
• Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
• Repair or replace the malfunctioning part.
If there is no common connector:
• Repair or replace the wiring harness which has a short to ground.
If the malfunction remains:
• Replace the PCM. (damage to driver in PCM)
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No
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Replace the high pressure fuel pump.
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13
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INSPECT FUEL PRESSURE (LOW-SIDE)
• Connect the fuel pressure gauge between fuel pump and high pressure fuel pump.
• Measure the low side fuel pressure.
• Is the low side fuel pressure within specification?
Specification:
• 545—695 kPa {5.56—7.08 kgf/cm2, 79.1—100.0 psi}
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Yes
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Go to the next step.
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No
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Inspect the following:
• Fuel line restriction
• Fuel filter clogged
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14
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INSPECT THROTTLE BODY FOR CLOGGING
• Visually inspect the throttle valve.
• Is any foreign material adhering around the throttle valve?
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Yes
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Clean the throttle valve.
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No
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Go to the next step.
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15
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INSPECT WASTEGATE VALVE
• Switch the ignition off.
• Inspect wastegate valve actuator.
• Is there any malfunction?
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Yes
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Replace the dynamic pressure turbo.
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No
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Go to the next step.
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16
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INSPECT ENGINE COMPRESSION
• Measure the compression pressure for each cylinder.
• Are compression pressures within specification?
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Yes
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Go to Step 22.
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No
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Go to the next step.
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17
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INSPECT ELECTRIC VARIABLE VALVE TIMING DRIVER
• Inspect the electric variable valve timing driver.
• Is there any malfunction?
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Yes
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Replace the electric variable valve timing motor/driver.
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No
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Go to the next step.
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18
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INSPECT ELECTRIC VARIABLE VALVE TIMING MOTOR
• Inspect the electric variable valve timing motor.
• Is there any malfunction?
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Yes
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Replace the electric variable valve timing motor/driver.
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No
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Go to the next step.
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19
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INSPECT ELECTRIC VARIABLE VALVE TIMING ACTUATOR
• Inspect the electric variable valve timing actuator.
• Is there any malfunction?
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Yes
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Replace the electric variable valve timing actuator.
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No
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Go to the next step.
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20
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INSPECT HYDRAULIC VARIABLE VALVE TIMING CONTROL SYSTEM OPERATION
• Perform the Hydraulic Variable Valve Timing Control System Operation Inspection.
• Is there any malfunction?
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Yes
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Repair or replace the malfunctioning part according to the inspection results.
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No
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Go to the next step.
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21
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INSPECT FOR MALFUNCTION DUE TO DEVIATED VALVE TIMING
• Inspect the valve timing (timing chain installation condition).
• Is the valve timing normal?
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Yes
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Inspect for the following engine internal parts:
• Cylinder
• Piston ring
• Intake valve
• Exhaust valve
• Such as cylinder head gasket
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No
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Adjust the valve timing to the correct timing.
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22
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VERIFY SPARK PLUG CONDITION
• Inspect the spark plug condition.
• Is the spark plug wet, covered with carbon or grayish white?
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Yes
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Spark plug is wet or covered with carbon:
• Perform the Spark Test.
Spark plug is grayish white:
• Inspect the fuel injector for restriction.
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No
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Go to the next step.
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23
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INSPECT THREE WAY SOLENOID VALVE INSPECTION
• Inspect three way solenoid valve.
• Is there any malfunction?
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Yes
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Replace the three way solenoid valve.
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No
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Go to the next step.
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24
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INSPECT EXHAUST SYSTEM FOR RESTRICTION
• Inspect for restriction in the exhaust system and the TWC.
• Is there any restriction?
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Yes
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Repair or replace the malfunctioning part according to the inspection results.
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No
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Go to the next step.
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25
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INSPECT IF MALFUNCTION CAUSE IS PCV VALVE OR INJECTOR DRIVER (PCM INTEGRATED)
• Inspect the PCV valve.
• Is there any malfunction?
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Yes
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Replace the PCV valve.
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No
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Injector driver malfunction.
• Replace the PCM.
If the problem remains, overhaul the engine.
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26
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Verify the test results.
• If normal, return to the diagnostic index to service any additional symptoms.
• If a malfunction remains, inspect the related Service Information and perform the repair or diagnosis.
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