2020 Cadillac CT4 Problems

The vehicle shudders and loses power when accelerating fast. My wife almost got hit when she pulled out in traffic the car stalled out. It is due to the cylinder deactivation (afm).

The contact owns a 2020 Cadillac CT4. The contact stated while driving 70 MPH, on several occasions, the vehicle failed to accelerate, hesitated, and then stalled. The vehicle was towed on three occasions to the local dealer, who was unable to determine the cause of the failure. There were no DTC codes retrieved. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The failure mileage was approximately 45,000.

I had two incidents with the Cadillac CT-4 in February and then again in April of 2026 of driving on I-75 at a highway speed of about 70 MPH when the vehicle suddenly downshifted and the engine revving at at very high RPM. The vehicle slowed down suddenly and it felt for a moment that I could not control the speed. The check engine light was on and the diagnostic indicated a transmission/engineer problem and to take in to service within a day. Both incidents in February and April felt the same. Both times I pulled over to the shoulder to shut the engine. I waited and in February it restarted without the engineer revving high. In April, it still revved high. When I took it to Ed Morse Cadillac in [XXX] in February 28, they indicated that it was a water pump failure and they replaced the water pump. I expressed that it was odd that a water pump could affect the vehicle engineer/transmission like it did when engine overheating is usually a warning of a water pump problem. The Odometer was at 73000 just over the 70000 warranty and Cadillac HQ agreed to pay for the repair. However, I continued to have the transmission problem or check engine light problem. I took it back several more times for the check engine light and even paid for a diagnostic. Ultimately, I had the same sudden downshift high engine rev on May 6th and brought it to the Brandon Cadillac again. This time they gave me a loaner and kept the car for a week and told me it was the transmission and that the core component would need to be replaced. The bill was for $4,449.83 for the repair on May 20, 2026. This time Cadillac HQ would not cover the repair even though there were other Cadiilacs with similar transmission issues. The Caddillac HQ Case Number is #XXX INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The vehicle shudders and loses power when accelerating fast. My wife almost got hit when she pulled out in traffic the car stalled out. It is due to the cylinder deactivation (afm).

The contact owns a 2014 Cadillac CT4. The contact stated that the "Service Safety Restraint System" message was displayed on the instrument panel while driving. The vehicle was taken to the dealer who diagnosed that the air bags needed to be replaced. The vehicle was not repaired due to the parts not yet being available. The manufacturer was not made aware of the failure. The approximate failure mileage was 3,000.

The electronic brake control module, break retainer, brake master cylinder and brake valve all failed. I was driving to lunch and coming down a hill when multiple warning lights turned on as I pressed the brakes. I had almost no braking power as I approached a stop sign that lets you enter a highway almost causing me to drive through the stop sign and into cross traffic. I had enough bearings to down shift it and slow it down enough to stop. If I have went through the stop sign, it could have been a fatal accident. The vehicle is at a GM dealership currently with all active codes and faulty equipment. I contacted GM and tried to get some help with this issue and they refuse to help since it is not on the recall list. There is a recall on these exact same parts on the exact same vehicle, GM said its VIN specific. The problem is still current. This vehicle is a major safety risk that obviously should have been included in the recall. There was no warning or no symptoms of this issue until the failure in the moment.

The vehicle shudders and loses power when accelerating fast. My wife almost got hit when she pulled out in traffic the car stalled out. It is due to the cylinder deactivation (afm).