Dodge Journey Overheating: Faulty Bypass Valve Alert

I had a very similar issue with my 2006 Dodge Caliber diesel. Speaking from someone with moderate experience working on cars, the symptoms you describe match exactly what I encountered. The engine overheating turned out to be a secondary issue caused by a faulty air intake sensor that was sending incorrect signals to the ECU. This caused the bypass valve to malfunction, leading to improper coolant circulation. My workshop found this during diagnostics and simply needed to reset the system after fixing the original sensor issue. Since it was directly related to a previous repair under warranty, I didnt have to pay anything. The engine stalling that followed the overheating was also resolved once they corrected the initial sensor problem. The exhaust system showed similar error codes at first, which made diagnosis tricky until they traced it back to the root cause. To help provide more specific advice for your case, could you share: Current mileage, Exact error codes stored in the ECU, Any recent repairs or maintenance done, Whether the overheating occurs more during idle or while driving, If there are any unusual sounds from the engine bay This information would help determine if your situation matches what I experienced with my Caliber.

Thanks for the detailed feedback on your Caliber experience. My Journey has 80127 KM on the clock with the last service completed just last month. The engine stalling and overheating seems most prominent during city driving. I checked under the hood and noticed small traces of coolant leak near the bypass valve assembly. No unusual sounds from the engine bay, but the temperature gauge fluctuates more than usual. The stored codes point to coolant temperature sensor issues, which aligns with what you experienced with the air intake sensor affecting the ECU readings. I agree that getting a proper diagnostic scan would help pinpoint if the root cause is similar to your case. Will book a workshop appointment to check both the sensor and bypass valve to improve fuel efficiency and prevent further overheating issues.

Thanks for providing those additional details about your Journey. The coolant leak you noticed near the bypass valve is actually a crucial finding that points to a different issue than what I had with my Caliber. The visible coolant leak combined with temperature fluctuations during city driving strongly suggests a physical failure rather than just a sensor issue. While my problem was resolved through sensor replacement and ECU reset, your symptoms indicate you likely have a deteriorating bypass valve seal or housing. A failing bypass valve can lead to serious engine overheating and potential power loss if not addressed promptly. The fact that its occurring mainly during city driving, where the cooling system cycles more frequently, supports this theory. Based on the somewhat similar experience with my Caliber, I recommend having the workshop: Pressure test the entire cooling system, Inspect the bypass valve assembly for crack propagation, Check the vacuum system integrity around the valve, Verify coolant levels and composition Getting this diagnosed quickly is important since coolant leaks can rapidly worsen and lead to more severe engine overheating. The repair costs for my sensor issue were covered under warranty, but a bypass valve replacement is typically a straightforward repair if caught early.

Appreciate the thorough response and diagnostic suggestions. The symptoms you describe with the bypass valve match what I am experiencing. The coolant leak seems more noticeable now, and the engine overheating continues especially in stop-and-go traffic. I scheduled a workshop visit for tomorrow morning. They will perform the pressure test and complete cooling system inspection as suggested. The service advisor mentioned they often see bypass valve failures causing similar overheating issues on these engines. Given the visible coolant leak and temperature fluctuations, I agree its likely a physical valve problem rather than just sensors. Will update once they diagnose the exact cause and complete repairs. The fuel efficiency has also dropped noticeably, so addressing this should help restore normal performance. Really helpful to compare experiences and confirm this is a known issue with a straightforward fix. Catching it early before more severe engine overheating occurs seems key based on your feedback.