Explorer Hybrid Exhaust Leak

I had similar symptoms with my Explorer. It sounds like a lambda sensor issue I experienced. When the sensor started to fail, it caused an imbalance in the air-fuel mixture, leading to rough running and a noticeable exhaust leak with a strong odor. Have you checked the sensor readings using an OBD2 scanner? Also, have you ruled out any DEF fluid system issues, if your vehicle has one?

Thanks for the insight. I haven't checked the lambda sensor readings with a scanner, but I will. How did you confirm that the lambda sensor was the problem? Were there specific error codes that indicated the defective sensor? Also, can a reasonably skilled person do the replacement, or should a mechanic do it?

My OBD2 scanner returned a specific code indicating a faulty lambda sensor. Also, the sensor's readings were erratic. Given the complexity of the exhaust treatment system, I'd advise taking your Explorer to a reputable shop for diagnosis and repair. Incorrect diagnosis or improper repair could lead to more significant and costly issues.

I appreciate the advice. I'll schedule an appointment with a trusted mechanic to diagnose and fix it. The repair cost 375€ and it was the Lambda sensor. Thanks again for your input.