2023 Jeep Grand Wagoneer Engine Problems

At engine idle with vehicle parked or driving in heavy traffic, exhaust fumes are entering the passenger compartment. I am not aware of any apparent exhaust leak. The fumes seem to be entering by way of the fresh air intake. I have confirmed CO readings with 2 different detection devices. If the vehicle is moving the readings have been 3-96 ppm. If the vehicle remains stopped with engine running, readings have been +100 ppm. This is a life safety concern. My local dealer had a service appointment over 1 week out 10/22/25. I asked Stellantis to escalate the case and have a reference number. # 94485584 I have lost the use of my vehicle and have not received a closer service appointment.

The contact owns a 2023 Jeep Grand Wagoneer. The contact stated that while his wife was driving approximately 65 MPH on the highway, the vehicle lost motive power and shut off. The vehicle was later towed to the local dealer, who diagnosed that the thermostat had failed, causing the engine to overheat. The contact was informed that the valve inside the thermostat had bound, causing improper internal operation of the thermostat. The thermostat was replaced, and the vehicle was repaired. The contact was informed that per TSB: 09-006-25, the same style thermostat was installed to repair the vehicle. The manufacturer was notified of the failure. The failure mileage was 17,500.

Vehicle over heated disabling vehicle on freeway. This was a know problem with this manufacturer.

2023 Grand wagonner : Vehicle overheats while driving and completely stops in the middle of the road with no time to pull over safely. This is the second time it has happened in a year of owning it. Check engine light has been on since the first time it overheated and dealers say they don't know why.

Engine shut down on highway while doing 55 mph. Almost was in a crash with multilabel cars. Second issue Forward Collision Warning failed on a sunny morning. A semi rolled and dumped it load causing the cars in front of me to stop suddenly. The Forward collision did nothing and did not apply my brakes. I missed the car in front of mine by a couple feet.

The contact owns a 2023 Jeep Grand Wagoneer. The contact stated while driving 75 MPH on a road trip, the vehicle made an abnormal beeping sound, failed to accelerate while depressing the accelerator pedal, and lost motive power. The messages "Power Steering Service Required" and "Electronic Stability Control Service Required" were displayed. Additionally, the check engine warning light was illuminated. The contact was able to veer to the side of the road. The vehicle failed to restart after several attempts. The vehicle was towed to the dealer, where it was it diagnosed that the pistons had failed, and the engine needed to be replaced. Additionally, the dealer diagnosed the vehicle and determined that coolant was leaking and had mixed with the engine oil. The vehicle was not repaired. The manufacturer was notified of the failure and offered assistance in covering engine replacement, and partial assistance in covering trip disruption and vehicle rental expenses. The failure mileage was approximately 5,994.