Diagnostic Test

PERFORM THE VVL SCAN TOOL DIAGNOSTICS

Turn the ignition on.
With the scan tool, navigate to Systems Tests, perform the VVL System Diagnostic test and follow the on screen directions.
NOTE:
Do not erase the DTC before running the routine.

When the test is complete, compare the results to the table below for the probable failure conditions.

Scan tool results:

Compare the results from the routine to the table below.

When the routine completes the results will display in a table showing each cylinder and the misfire percentage result for each cylinder during the three tests that were performed. At the top will be a general description of the possible issue or issues. For a more detailed description compare the misfire percentage data recorded to the table below for a detailed list of the probable causes. NOTE: Only count the misfire percentages that are above 75-80% when looking up the results in the table. Any percentage below 75% should not be factored into the result table .

SCAN TOOL INTRUSIVE VVL TEST RESULT	PROBABLE CAUSES	REPAIR ACTIONS
Low misfire percentage on (1) Rocker Stuck Low test, (2) Rocker Stuck High, Low RPM test, and (3) Rocker Stuck High, High RPM test	No VVL issue detected	The misfire condition being detected is not caused by the VVL System. Another system is likely causing the misfire
High misfire percentage on (1) Rocker Stuck Low test, (2) Rocker Stuck High, Low RPM test, and (3) Rocker Stuck High, High RPM test	No VVL issue detected	The misfire condition being detected is not caused by the VVL System. Another system is likely causing the misfire
(1) Rocker Stuck Low test - has high misfire percentage on Cylinder 1	VVL Solenoid 1/1 stuck on/open VVL Solenoid 1/1 control circuit shorted to 12 volts VVL Solenoid 1/1 has missing or damaged supply O-ring causing oil pressure leakage from the supply oil passage to the control oil passage Cylinder 1 rocker arm lash adjuster issue (stuck or broken) Cylinder 1 rocker arm lock pin stuck retracted Oil pressure leakage from the supply oil passage to the front control oil passage in the Cylinder Head.	Verify that the VVL Solenoid 1/1 control circuit is not shorted to 12 volts Check operation of VVL Solenoid 1/1 for a stuck on/open condition, damaged or missing supply O-ring Check for broken or stuck Cylinder 1 rocker arms or lock pins It is a very low percentage of the time that an internal crack in a Cylinder Head would cause this issue. However if all other possible causes are exhausted, replace the Cylinder Head.
(1) Rocker Stuck Low test - has high misfire percentage on Cylinder 2	VVL Solenoid 2/1 stuck on/open VVL Solenoid 2/1 control circuit shorted to 12 volts VVL Solenoid 2/1 has missing or damaged supply O-ring causing oil pressure leakage from the supply oil passage to the control oil passage Cylinder 2 rocker arm lash adjuster issue (stuck or broken) Cylinder 2 rocker arm lock pin stuck retracted Oil pressure leakage from the supply oil passage to the front control oil passage in the Cylinder Head.	Verify that the VVL Solenoid 2/1 control circuit is not shorted to 12 volts Check operation of VVL Solenoid 2/1 for a stuck on/open condition, damaged or missing supply O-ring Check for broken or stuck Cylinder 2 rocker arms or lock pins It is a very low percentage of the time that an internal crack in a Cylinder Head would cause this issue. However if all other possible causes are exhausted, replace the Cylinder Head. Proceed to step below to check the oil pressure in the Cylinder Head. Refer to 2.
(1) Rocker Stuck Low test - has high misfire percentage on Cylinder 3	Cylinder 3 rocker arm lash adjuster issue (stuck or broken) Cylinder 3 rocker arm lock pin stuck retracted	Check for broken or stuck Cylinder 3 rocker arms or lock pins
(1) Rocker Stuck Low test - has high misfire percentage on Cylinder 4	Cylinder 4 rocker arm lash adjuster issue (stuck or broken) Cylinder 4 rocker arm lock pin stuck retracted	Check for broken or stuck Cylinder 4 rocker arms or lock pins
(1) Rocker Stuck Low test - has high misfire percentage on Cylinder 5	Cylinder 5 rocker arm lash adjuster issue (stuck or broken) Cylinder 5 rocker arm lock pin stuck retracted	Check for broken or stuck Cylinder 5 rocker arms or lock pins
(1) Rocker Stuck Low test - has high misfire percentage on Cylinder 6	Cylinder 6 rocker arm lash adjuster issue (stuck or broken) Cylinder 6 rocker arm lock pin stuck retracted	Check for broken or stuck Cylinder 6 rocker arms or lock pins
(1) Rocker Stuck Low test - high misfire percentage on Cylinder 3 and Cylinder 5	VVL Solenoid 1/2 stuck on/open VVL Solenoid 1/2 control circuit shorted to 12 volts VVL Solenoid 1/2 has missing or damaged supply O-ring causing oil pressure leakage from the supply oil passage to the control oil passage Oil pressure leakage from the supply oil passage to the rear control oil passage in the Cylinder Head. NOTE: It's less likely but possible for a rocker arm lash adjuster failure (stuck or broken) or lock pin stuck retracted on both Cylinder 3 and Cylinder 5	Check the VVL Solenoid 1/2 control circuit for a short to 12 volts condition Check operation of VVL Solenoid 1/2 for a stuck on/open condition, damaged or missing supply O-ring It is a very low percentage of the time that an internal crack in a Cylinder Head would cause this issue. However if all other possible causes are exhausted, replace the Cylinder Head.
(1) Rocker Stuck Low test - high misfire percentage on Cylinder 4 and Cylinder 6	VVL Solenoid 2/2 stuck on/open VVL Solenoid 2/2 control circuit shorted to 12 volts VVL Solenoid 2/2 has missing or damaged supply O-ring causing oil pressure leakage from the supply oil passage to the control oil passage Oil pressure leakage from the supply oil passage to the rear control oil passage in the Cylinder Head. NOTE: It's less likely but possible for a rocker arm lash adjuster failure (stuck or broken) or lock pin stuck retracted on both Cylinder 4 and Cylinder 6	Check the VVL Solenoid 2/2 control circuit for a short to 12 volts condition Check operation of VVL Solenoid 2/2 for a stuck on/open condition, damaged or missing supply O-ring It is a very low percentage of the time that an internal crack in a Cylinder Head would cause this issue. However if all other possible causes are exhausted, replace the Cylinder Head. Proceed to step below to check the oil pressure in the Cylinder Head. Refer to 2.
(1) Rocker Stuck Low test - high misfire percentage Cylinder 1, Cylinder 3, and Cylinder 5	Both bank 1 solenoids have missing or damaged supply O-ring causing oil pressure leakage from the supply oil passage to the control oil passage for both bank 1 solenoids Oil pressure leakage from the supply oil passage to the front and rear control oil passages in the Cylinder Head.	Check operation of VVL Solenoid 1/2 for a stuck on/open condition, damaged or missing supply O-ring It is a very low percentage of the time that an internal crack in a Cylinder Head would cause this issue. However if all other possible causes are exhausted, replace the Cylinder Head. Proceed to step below to check the oil pressure in the Cylinder Head. Refer to 2.
(1) Rocker Stuck Low test - high misfire percentage Cylinder 2, Cylinder 4, and Cylinder 6	Both bank 2 solenoids have missing or damaged supply O-ring causing oil pressure leakage from the supply oil passage to the control oil passage for both bank 2 solenoids Oil pressure leakage from the supply oil passage to the front and rear control oil passages in the Cylinder Head.	Check operation of VVL Solenoid 2/2 for a stuck on/open condition, damaged or missing supply O-ring It is a very low percentage of the time that an internal crack in a Cylinder Head would cause this issue. However if all other possible causes are exhausted, replace the Cylinder Head. Proceed to step below to check the oil pressure in the Cylinder Head. Refer to 2.
(1) Rocker Stuck Low test - high misfire percentage for all Cylinders (1 - 6)	Missing or damaged supply O-rings causing oil pressure leakage from the supply oil passage to the control oil passage for front and rear solenoids on bank 1 and bank 2 Oil pressure leakage from the supply oil passage to the front and rear control oil passages in both Cylinder Heads.	Check operation of all VVL Solenoids for a stuck on/open condition, damaged or missing supply O-rings It is a very low percentage of the time that an internal crack in a Cylinder Head would cause this issue. However if all other possible causes are exhausted, replace both Cylinder Heads.
(2) Rocker Stuck High, Low RPM test, or (3) Rocker Stuck High, High RPM test - high misfire percentage Cylinder 1	VVL Solenoid 1/1 control circuit open or shorted to ground VVL Solenoid 1/1 stuck closed/off VVL Solenoid 1/1 has missing or damaged control O-ring causing oil pressure leakage from the control oil passage to the exhaust oil passage Control oil passage pressure restricted Cylinder 1 lash adjuster plugged Cylinder 1 rocker arm lash adjuster issue (stuck or broken) Cylinder 1 rocker arm lock pin stuck extended	Check the VVL Solenoid 1/1 control circuit for an open or shorted to ground condition Check the VVL Solenoid 1/1 for a missing or damaged control O-ring Actuate and check the VVL Solenoid 1/1 operation. Check for debris on screen Cylinder 1 lash adjuster plugged Cylinder 1 rocker arm stuck failure or lock pin stuck extended
(2) Rocker Stuck High, Low RPM test, or (3) Rocker Stuck High, High RPM test - high misfire percentage Cylinder 2	VVL Solenoid 2/1 stuck closed/off VVL Solenoid 2/1 control circuit open or shorted to ground VVL Solenoid 2/1 has missing or damaged control O-ring causing oil pressure leakage from the control oil passage to the exhaust oil passage Control oil passage pressure restricted Cylinder 2 lash adjuster plugged Cylinder 2 rocker arm lash adjuster issue (stuck or broken) Cylinder 2 rocker arm lock pin stuck extended	Check the VVL Solenoid 2/1 control circuit for an open or shorted to ground condition Check the VVL Solenoid 2/1 for a missing or damaged control O-ring Actuate and check the VVL Solenoid 2/1 operation. Check for debris on screen Cylinder 2 lash adjuster plugged Cylinder 2 rocker arm stuck failure or lock pin stuck extended
(2) Rocker Stuck High, Low RPM test, or (3) Rocker Stuck High, High RPM test - high misfire percentage Cylinder 3	Cylinder 3 lash adjuster plugged Cylinder 3 rocker arm lash adjuster issue (stuck or broken) Cylinder 3 rocker arm lock pin stuck extended	Cylinder 3 lash adjuster plugged Cylinder 3 rocker arm stuck failure or lock pin stuck extended
(2) Rocker Stuck High, Low RPM test, or (3) Rocker Stuck High, High RPM test - high misfire percentage Cylinder 4	Cylinder 4 lash adjuster plugged Cylinder 4 rocker arm lash adjuster issue (stuck or broken) Cylinder 4 rocker arm lock pin stuck extended	Cylinder 4 lash adjuster plugged Cylinder 4 rocker arm stuck failure or lock pin stuck extended
(2) Rocker Stuck High, Low RPM test, or (3) Rocker Stuck High, High RPM test - high misfire percentage Cylinder 5	Cylinder 5 lash adjuster plugged Cylinder 5 rocker arm lash adjuster issue (stuck or broken) Cylinder 5 rocker arm lock pin stuck extended	Cylinder 5 lash adjuster plugged Cylinder 5 rocker arm stuck failure or lock pin stuck extended
(2) Rocker Stuck High, Low RPM test, or (3) Rocker Stuck High, High RPM test - high misfire percentage Cylinder 6	Cylinder 6 lash adjuster plugged Cylinder 6 rocker arm lash adjuster issue (stuck or broken) Cylinder 6 rocker arm lock pin stuck extended	Cylinder 6 lash adjuster plugged Cylinder 6 rocker arm stuck failure or lock pin stuck extended
(2) Rocker Stuck High, Low RPM test, or (3) Rocker Stuck High, High RPM test - high misfire percentage Cylinder 3 and Cylinder 5	VVL Solenoid 1/2 stuck closed/off VVL Solenoid 1/2 control circuit open or shorted to ground VVL Solenoid 1/2 has missing or damaged control O-ring causing oil pressure leakage from the control oil passage to the exhaust oil passage Control oil passage pressure restricted NOTE: It's less likely but possible for a rocker arm lash adjuster issue (stuck or broken) or lock pin stuck retracted on Cylinder 3 and Cylinder 5	Check the VVL Solenoid 1/2 control circuit for an open or shorted to ground condition Check the VVL Solenoid 1/2 for a missing or damaged control O-ring Actuate and check the VVL Solenoid 1/2 operation. Check for debris on screen Cylinder 3 or 5 lash adjuster plugged Cylinder 3 or 5 rocker arm stuck failure or lock pin stuck extended
(2) Rocker Stuck High, Low RPM test, or (3) Rocker Stuck High, High RPM test - high misfire percentage Cylinder 4 and Cylinder 6	VVL Solenoid 2/2 stuck closed/off VVL Solenoid 2/2 control circuit open or shorted to ground VVL Solenoid 2/2 has missing or damaged control O-ring causing oil pressure leakage from the control oil passage to the exhaust oil passage Control oil passage pressure restricted NOTE: It's less likely but possible for a rocker arm lash adjuster issue (stuck or broken) or lock pin stuck retracted on Cylinder 4 and Cylinder 6	Check the VVL Solenoid 2/2 control circuit for an open or shorted to ground condition Check the VVL Solenoid 2/2 for a missing or damaged control O-ring Actuate and check the VVL Solenoid 2/2 operation. Check for debris on screen Cylinder 4 or 6 lash adjuster plugged Cylinder 4 or 6 rocker arm stuck failure or lock pin stuck extended
(2) Rocker Stuck High, Low RPM test, or (3) Rocker Stuck High, High RPM test - high misfire percentage Cylinder 1, Cylinder 3 and Cylinder 5	VVL Solenoid 1/1 and 1/2 have missing or damaged control O-rings causing oil pressure leakage from the control oil passage to the exhaust oil passage Bank 1 oil supply passage blockage or restriction to front and rear oil feeds in the bank 1 Cylinder Head Large internal leakage in bank 1 Cylinder Head affecting the front and rear oil feeds	Check the control O-rings on the front and rear bank 1 VVL Solenoids for damage Check for proper oil pressure at the front and rear bank 1 VVL Solenoids. Proceed to step below to check the oil pressure in the Cylinder Head. Refer to 2. It is a very low percentage of the time that an internal crack in a Cylinder Head would cause this issue. However if the oil pressure is low to both solenoids and all other possible causes are exhausted, replace the Cylinder Head NOTE: Low oil pressure in the Cylinder Head will likely also cause issues/faults for the VVT system
(2) Rocker Stuck High, Low RPM test, or (3) Rocker Stuck High, High RPM test - high misfire percentage Cylinder 2, Cylinder 4 and Cylinder 6	VVL Solenoid 2/1 and 2/2 have missing or damaged control O-rings causing oil pressure leakage from the control oil passage to the exhaust oil passage Bank 2 oil supply passage blockage or restriction to front and rear oil feeds in the bank 2 Cylinder Head Large internal leakage in bank 2 Cylinder Head affecting the front and rear oil feeds	Check the control O-rings on the front and rear bank 2 VVL Solenoids for damage Check for proper oil pressure at the front and rear bank VVL Solenoids. Proceed to step below to check the oil pressure in the Cylinder Head. Refer to 2. It is a very low percentage of the time that an internal crack in a Cylinder Head would cause this issue. However if the oil pressure is low to both solenoids and all other possible causes are exhausted, replace the Cylinder Head NOTE: Low oil pressure in the Cylinder Head will likely also cause issues/faults for the VVT system
(2) Rocker Stuck High, Low RPM test, or (3) Rocker Stuck High, High RPM test - high misfire percentage for all Cylinders (1 - 6)	Engine oil pressure too low to both Cylinder Heads due to: Oil level low Wrong viscosity oil Oil Filter restriction Engine mechanical failure (damaged bearings, pick-up tube or seal, engine block, etc.) Faulty Oil Pump	Check for proper oil level, filter and viscosity before checking engine oil pressure If the engine oil pressure is low check for any mechanical issue that could cause low oil pressure. If there are no issues with the bearings, pick-up tube and engine block replace the Engine Oil Pump Assembly NOTE: Low engine oil pressure will likely also cause issues/faults for the VVT system

CHECK THE ACTUAL OIL PRESSURE TO THE VVL SOLENOID IN THE CYLINDER HEAD
1. Turn the ignition off.
2. Remove the appropriate VVL Solenoid called out by the scan tool.
3. Install the (special tool #2027300090, Kit, VVL Adapters) in place of the VVL Solenoid.
4. Start the engine and allow it to idle.
5. With the scan tool, monitor the Dual Oil Pump mode.
  NOTE:
  Let the engine run long enough for the pump to switch to low pump mode.
6. Read and record the oil pressure reading on the oil pressure gauge. Compare the reading to the main engine oil pressure reading from the Engine Oil Pressure Sensor reading on the scan tool.
  NOTE:
  The Cylinder Head oil pressure should be within 5.0 psi of main engine oil pressure reading.
  
  Is the Cylinder Head oil pressure should be within 5.0 psi of main engine oil pressure?
  
  Yes
  - Remove and inspect the screen on the VVL Solenoid for debris that can block oil flow through the solenoid. Check the seals on the VVL Solenoid for damage and proper installation. If no debris is found, and the seals appear good replace the VVL Solenoid in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Diagnose and repair the lack of oil pressure to the VVL Solenoid.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .