Diagnose and Fix 3rd Generation Wrangler Issues
Common Jeep Wrangler JK problems include water leaking from the ceiling or doors on the driver or passenger side, a leaky valve cover gasket, and heater problems from a clogged heater core. Find out what causes these and other common issues on the 2007 to 2018 Jeep Wrangler as our experts review the top 5 problems with the 3rd generation Wrangler.
Top 5 Issues on the 3rd Gen Jeep Wrangler JK (2007-2018)
1. Bad Heater Core in Wrangler JK
Symptoms of a Bad Heater Core
- Heat isn’t working as well or is not working
Causes of a Bad Heater Core
A clogged or plugged heater core is usually the cause of heating problems
How to Fix a Bad Heater Core
- You can remove the lines going into the heater core and clean out the heater core with a garden hose without applying too much pressure
- You may have to replace the heater core, which is a detailed job and includes removing the dash
- Prevent interior heating issues by changing the coolant regularly, and remove the heater core hoses and run fresh water through them with each coolant change.
2. EVAP System Codes
Signs the Jeep Wrangler JK has EVAP System Problems
- Check engine light is on for an EVAP system code
Causes of EVAP System Codes
The gas cap is usually the cause for an EVAP code but it could be the leak detection pump in the EVAP canister.
How to Fix EVAP System Codes
- Check the gas cap first. Wiggle it to see if it’s loose. Inspect the gasket for dryness or rotting and check how it ratchets.
- The leak detection pump is in the canister at the back. It is similar to an EVAP vent valve. Replace the valve and clear the code.
3. Valve Cover Gasket Leak
Symptoms of a Valve Cover Gasket Leak
- Burning oil smell
- Oil dripping on the ground
- Oil dripping from the valve cover gasket
Causes of a Valve Cover Gasket Leak
Oil tends to leak from the valve cover gasket on the 07-18 Jeep Wrangler. The valve cover gasket is difficult to reach and requires the removal of several parts.
How to Fix the Valve Cover Gasket Leak
4. Faulty Oxygen (O2) Sensors
Symptoms of Faulty O2 Sensors
- Rough running engine
- Check engine light for oxygen sensors
Causes of Faulty O2 Sensors
If there is an O2 sensor code on the 3rd gen Wrangler, chances are the O2 sensor needs to be replaced
How to Fix Faulty O2 Sensors
Replace the O2 sensors as soon as possible. Not replacing them could cause damage to the catalytic converter, which is expensive to replace.
5. Water Leaks
Signs the 2007 to 2018 Wrangler JK Has Problems with Water Leaks
- Water leaking past the ceiling gasket and the door gasket
- Water on the carpet underneath the floor mat
Causes of Water Leaks
Sometimes water can leak past the ceiling and the door gasket. Sometimes it’s not an issue with the gasket but the design.
How to Fix Water Leaks
You may have to add foam with tape on the backside to the gasket to cover areas that may not be filled even if a new gasket is installed.
Fix Your Jeep Wrangler JK Problems Yourself
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Model Years of the Jeep Wrangler JK
- 2007 Jeep Wrangler
- 2008 Jeep Wrangler
- 2009 Jeep Wrangler
- 2010 Jeep Wrangler
- 2011 Jeep Wrangler
- 2012 Jeep Wrangler
- 2013 Jeep Wrangler
- 2014 Jeep Wrangler
- 2015 Jeep Wrangler
- 2016 Jeep Wrangler
- 2017 Jeep Wrangler
- 2018 Jeep Wrangler
