Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Diagnostic Test
- CHECKING THE EXHAUST SYSTEM FOR LEAKS
Turn the ignition off.
Raise the vehicle in accordance with the Service Information.
WARNING: The normal operating temperature of the exhaust system is very high. Never work around or attempt to service any part of the exhaust system until it has cooled. Special care should be taken when working near the catalytic converter. The temperature of the converter rises to a high level after a short period of engine operating timeConnect Exhaust Cone #8404-EC to Air Pressure Regulator (with hose) #W-18-MIL-1146AS.
CAUTION: The air pressure must not exceed 27.6 KPA (4 psi), otherwise engine damage can occur.Attach shop air to the air pressure regulator.
Adjust the Air Pressure Regulator to 27.6 KPA (4 psi)
Insert the exhaust cone into the vehicle tail pipe.
If equipped with dual exhaust, plug the other exhaust pipe.
Apply Mopar® Air Leak Detector (or equivalent) to the following areas:
- All welded joints from 6 inches rearward of the downstream O2 sensor forward
- O2 sensor seal points
- O2 sensor boss welds
- Flange/joint connection(s)
- Exhaust manifold to cylinder head connection(s)
- EGR solenoid gasket base and tube seal points (if equipped)
Watch for the leak detector solution water to bubble.
Use the following definitions to help determine if system or component repair/replacement is necessary:
Type 1 Leak is defined as a leak where very small foam like bubbles approximately 1 mm (0.04 in.) or less appear.
Any Type 1 or greater leaks found in welded joints, O2 sensor seal points or O2 sensor boss welds must be repaired or the component must be replaced.
Type 2 Leak is defined as a leak where larger, pea size bubbles, approximately 8mm (0.31 in.) or greater appear.
Any Type 2 or greater leaks found in flange or joint connections, exhaust manifold to cylinder head connections, or EGR gasket and tube seal points must be repaired or the components must be replaced
Leak Location Repair required if results at 4 psi reveal bubble size: Welded joints Type 1: 1 mm (0.04 in.) or greater O2 Sensor seal points Type 1: 1 mm (0.04 in.) or greater O2 Sensor boss welds Type 1: 1 mm (0.04 in.) or greater Flange / joint connections Type 2: 8 mm (0.31 in.) or greater Exhaust Manifold to cylinder head connections Type 2: 8 mm (0.31 in.) or greater EGR gasket and tube seal points Type 2: 8 mm (0.31 in.) or greater If a leak is found that matches the above definition, repair or replace the component as necessary.
Once the repair is complete, repeat the procedure to verify that all leaks have been repaired.
Were any exhaust leaks found?
Yes
- Repair or replace the leaking exhaust parts as necessary.
- Perform PCM VERIFICATION TEST .
No
- Test complete.
NO RELATED
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.