Diagnostic Test
WARNING: This page is about a different car, the 2017 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK FOR AN ACTIVE DTC
- Start the engine.
- Allow the engine to reach normal operating temperature.
- Test drive the vehicle in accordance with the when monitored conditions.
- With the scan tool, read DTCs and record on the repair order.
Is the DTC active or pending?
Yes
- Go To 2
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
- CHECK FOR AN INTAKE MANIFOLD LEAK AT A SPECIFIC CYLINDER ON BANK 1
- Check for any of the following conditions:
- Intake manifold seals leaking at a specific cylinder.
- Intake plenum leak at a specific cylinder.
- Warped/cracked Intake Manifold or plenum.
- Vacuum leak at a Fuel Injector O-Rings.
Were any Intake or vacuum leak issues found?
Yes
- Perform the appropriate Intake or vacuum leak repairs in accordance with the Service Information.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .
No
- Go To 3
- Check for any of the following conditions:
- CHECK FOR ISSUES THAT COULD CAUSE A FUEL INJECTOR IMBALANCE ISSUE ON BANK 1
- Check for any of the following conditions, but not limited to:
- Verify correct voltage supply at each Fuel Injector.
- Verify correct control circuit operation at each Fuel Injector.
- Verify correct Fuel Injector operation (spray pattern).
Were any Fuel Injector, voltage supply, or injector (spray pattern) issues found?
Yes
- Repair the Fuel Injector voltage supply, control circuit, or injector (spray pattern) as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .
No
- Go To 4
- Check for any of the following conditions, but not limited to:
- CHECK CYLINDER COMPRESSION AND IGNITION OPERATION ON BANK 1
- Perform a cylinder compression and/or cylinder leak down test on each cylinder on bank 1.
- Check the ignition system for any of the following conditions, but not limited to:
- Verify correct voltage supply at each Ignition Coil.
- Verify correct control circuit operation at each Ignition Coil.
- Verify that the Spark Plugs are matching and are equivalent to OEM specifications.
- Verify correct Spark Plug gap.
- Visually inspect the Ignition Coils and Spark Plugs for signs of carbon tracking.
- Visually inspect the Ignition Coils for signs of damage.
Were any cylinder compression or ignition system issues found?
Yes
- Repair the cylinder compression or ignition system issues as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .
No
- Go To 5
- CLEAN CARBON DEPOSITS FROM ENGINE CYLINDERS
- Using the Mopar Combustion cleaner, de-carbon the engine.
- After driving and clearing the combustion cleaner from the engine, erase DTCs with the scan tool.
- Test drive the vehicle in accordance with the when monitored conditions.
- With the scan tool, read DTCs.
Did the DTC return?
Yes
- Go To 6
No
- Repair is complete.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .
- CHECK FOR VALVETRAIN AND VARIABLE VALVE SYSTEM ISSUES
- Check the valvetrain for any of the following conditions:
- Verify correct operation of the Multi Air system.
- Check for broken, worn or improperly installed valve springs.
- Check for broken, worn or improperly installed Camshaft followers.
- Check for worn Camshaft lobes.
Were any valvetrain and variable valve system issues found?
Yes
- Repair the valvetrain and variable valve system issues as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .
No
- Go To 7
- Check the valvetrain for any of the following conditions:
- REPLACE THE BANK 1 UPSTREAM O2 SENSOR AND RETEST FOR DTCS
- Replace the Bank 1 Upstream O2 Sensor in accordance with the Service Information. Refer to SENSOR, OXYGEN, INSTALLATION, 3.2L .
- Turn the ignition on.
- With the scan tool, erase DTCs.
- Using the Freeze Frame Data or When Monitored Conditions above, operate the vehicle within the conditions that set the DTC.
- With the scan tool, read DTCs.
Did the DTC return?
Yes
- Go To 8
No
- Replacing the Bank 1 Upstream O2 Sensor repaired the fault.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .
- CHECK RELATED PCM AND COMPONENT CONNECTIONS
- Perform any Service Bulletins that apply.
- Disconnect all PCM harness connectors.
- Disconnect all related in-line harness connections (if equipped).
- Disconnect the related component harness connectors.
- Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
- Proper connector installation.
- Damaged connector locks.
- Corrosion.
- Other signs of water intrusion.
- Weather seal damage (if equipped).
- Bent terminals.
- Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
- Terminals that have been pushed back into the connector cavity.
- Check for spread terminals and verify proper terminal tension.
Repair any conditions that are found.
- Reconnect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
- Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
- Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
- With the scan tool, erase DTCs.
- Test drive or operate the vehicle in accordance with the when monitored and set conditions.
- With the scan tool, read DTCs.
Did the DTC return?
Yes
- Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL (PCM), REMOVAL, 2.4L/3.2L .
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .
No
- The wiring or poor connection problem has been repaired.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .