2026 Jeep Grand Cherokee L Complaints

I am the owner of a 2026 Jeep Grand Cherokee L equipped with the 2.0L Hurricane 4 Turbo engine. At approximately 3,500 miles, the vehicle experienced a spark plug failure/breakage. The vehicle was taken to Nyle Maxwell dealership in Austin, Texas, where a spark plug was found broken and was replaced under warranty on 5/15/2026 after a lengthy wait for the parts of 11 days. This same failure occurred a second time at approximately 4,900 miles on 7/13/2026. The vehicle was again taken to the Nyle Maxwell dealership for repair. Both failures occurred while operating the vehicle on 87 octane regular unleaded fuel, which is the fuel grade stated as acceptable in the owner’s manual. I am concerned this is a widespread issue, as other owners of this same engine report similar spark plug failures using 87 octane fuel, per online owner forums. I am filing this complaint to document the pattern and request that NHTSA investigate.

New 2026 Jeep Grand Cherokee overheated at 1,900 miles; engine hit red zone, A/C shut off, coolant low\. Vehicle towed\. Request full warranty repair, diagnosis, and reimbursement for towing, rental, and hotel costs\.

While driving my 2026 Jeep Grand Cherokee, the check engine light began flashing (a flashing, rather than steady, check engine light typically indicates an active engine misfire). At or around the same time, the vehicle began shaking/vibrating noticeably, consistent with the misfire condition indicated by the flashing light. Separately, I experienced a failure of the vehicle’s push-button Start/Stop ignition system. When attempting to shut the engine off by pressing the Start/Stop button, the engine did not turn off as expected. The button had to be pressed several times before the engine finally powered off.

While driving from Tampa to Miramar Beach, Florida, the vehicle operated normally on the highway. However, shortly after exiting the highway and driving in slow traffic, the engine temperature gauge suddenly rose into the red zone, and the air conditioning automatically shut off. I immediately pulled over and allowed the vehicle to cool. The engine temperature returned to normal, and after the engine cooled completely, I found that the coolant reservoir level was only slightly below the MIN mark. There are no visible coolant leaks, no check engine light, and no warning messages currently displayed.

Cylinder Miss fire at idle due to damaged spark plugs