2021-2025 Alfa Romeo Tonale Coolant Leak & Overheating Issue

Mopar has identified a recurring "Coolant Leak & Engine Overheating Issue" affecting several models, including the 2021-2025 Alfa Romeo Tonale, Jeep Wrangler (JL), Jeep Grand Cherokee (WL), Jeep Compass (MP), and Dodge Hornet (GG). This issue specifically pertains to vehicles equipped with the GME T4 DOHC engine. The manufacturer recommends a detailed diagnostic approach to pinpoint the root cause before resorting to a complete engine replacement.

Symptoms of a Coolant Leak or Overheating

Owners may notice various indicators suggesting a coolant leak or engine overheating. These can include a low coolant level visible in the reservoir, the vehicle failing to start, experiencing power or torque degradation, an increase in misfire events, or the illumination of the check engine light. If you observe any of these symptoms in your Alfa Romeo Tonale coolant leak, it is crucial to have your vehicle inspected promptly.

Diagnosis for Engine Overheating

Before any major repairs, Mopar outlines a series of pre-checks and detailed diagnostic steps for technicians. These procedures are designed to accurately identify the source of the problem:

Pre-Checks

• Coolant Level: Verify and record the coolant level in the coolant bottle.
• Cooling System Components: Inspect the thermostat and other related components, such as the water pump and cooling fan, for any issues.
• Oil Sample: Drain a sample of engine oil to check for the presence of coolant or moisture, which indicates an internal leak.

Detailed Checks

• Cylinder Leakage Test: Perform this test on all cylinders by pressurizing each cylinder at Top Dead Center (TDC) with 5.5 bar (83 PSI) of air. Technicians should then check for bubbles in the radiator coolant, which would indicate a leak within the combustion chamber.
• Coolant Pressurization Test: Pressurize the cooling system to 2 bar (30 PSI) and hold for one hour, checking for any leak down. A borescope should also be used to inspect the cylinders for coolant presence in the combustion chamber.
• CO2 Leak Test: Conduct a CO2 leak test to detect combustion gases in the cooling system, which can indicate a head gasket issue or a cracked cylinder head.

Common Causes of Coolant Leaks

If the diagnostic checks do not indicate a need for a long block or complete engine replacement, the issue likely stems from specific components. Mopar highlights several common culprits for the Alfa Romeo Tonale coolant leak and overheating problem:

• Water Pump Inlet Pipe: Loose bolts or improper torque on the water pump inlet pipe (refer to CSN ZD8 for guidance).
• Water Pump Gasket: A twisted water pump gasket inside its groove.
• Thermostat Column Manifold: Loose bolts or improper torque on the thermostat column manifold.
• Cylinder Block Casting: Porosity or cracks in the cylinder block casting, particularly near the combustion chamber.
• Oil Coolant Exchanger: Internal cracks in the oil coolant exchanger, which can lead to coolant and oil mixing.

Affected Long Block Part Numbers

For cases where a long block replacement is deemed necessary, Mopar provides a list of applicable part numbers:

• 18-24MY JL ESS: PN 68731685AA
• 21-24MY JL PHEV: PN 68731693AA
• 22-24MY WL PHEV: PN 68731694AA
• 23-25MY MP / 23-25MY GG/GC: PN 68731712AA

Important Warnings for Owners

Mopar's newsletter includes critical information regarding warranty coverage and repair expectations that owners should be aware of:

• Unnecessary Engine Replacement: "If none of these checks (1-2-3) fails, it does not need a long block (or a complete engine) but just the component causing the coolant leak, more likely ones listed below." This emphasizes that a full engine replacement is often not required if specific component failures are identified.
• Fuse Replacements: "Blown fuses, when not included in an electrical wiring repair, are NOT covered under the warranty." Additionally, "Warranty claims that are for fuses only (claims that have no other justifiable electrical repair), will be charged back with a statement of 'Fuses alone are considered a maintenance cost and are not a warrantable component.'" This applies to issues like a "110 power outlet inoperable" or "the USB outlet is inoperable" where only a fuse is replaced without an underlying electrical repair.
• TSB Application Guidelines: For issues like those covered by TSB 08-136-24 (related to the 2023-2024 Jeep Compass), technicians are instructed to apply the bulletin only if a Malfunction Indicator Lamp (MIL) is present or reported by the customer, and on a DTC basis. This prevents unnecessary software updates.
• Brake Pedal Switch Stuck Condition: For 2023-2025 MY (VF) vehicles experiencing a "Brake Pedal Switch Stuck Condition" with symptoms like "brake lights remaining ON" or the vehicle starting without pressing the brake pedal, specific DTCs P057B, P0572, P0703 may be present. Owners should be aware that improper uninstallation of the switch can cause further damage.

NHTSA ID: 11011962