Which parts fail
Components named in complaints (accelerator pedal, throttle, sudden acceleration, cruise control).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2018 Chevrolet Malibu owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2018 Chevrolet Malibu. The contact stated that while driving very slowly into a parking space, the brake pedal was pressed to stop the vehicle, but the vehicle experienced unintended acceleration and suddenly accelerated forward at a very high rate of speed and crashed into a furniture store showroom window. During the incident, the front end of the vehicle was severely damaged, but no air bags deployed. No injuries were reported. A police report was taken at the scene, and the vehicle was towed to the local dealer. The cause of the failure was not yet determined. The manufacturer was not yet contacted. The failure mileage was 80,000.
The contact owns a 2018 Chevrolet Malibu. The contact stated that a "shift to park turn the vehicle off" message was displayed while the vehicle was in the park position. While driving at unknown speeds, the vehicle stalled. The steering wheel was tight. After slowing down, the driver depressed the start/stop button, and the vehicle shut off and restarted. The vehicle was randomly shut down. After waiting, the vehicle restarted. While depressing the brake pedal, there was an abnormal, unidentifiable noise detected, and the vehicle came to a sudden halt. While driving at 55 mph, the vehicle suddenly stopped, and she hit her head on the steering wheel but medical attention was not provided. The vehicle was pulsating while driving. There was a sound of water going through the vehicle. The vehicle was slow to accelerate and then moved violently. …
The contact owns a 2018 Chevrolet Malibu. The contact stated while driving approximately 65 MHP, the message "Engine Power Reduced" was displayed and the vehicle decelerated to 30 MPH. The contact stated that the speed would no longer exceed 30 MPH. The cause of the failure was not yet determined. The manufacturer was notified of the failure, but no assistance was offered. The local dealer was not contacted. The contact stated that the failure had also previously occurred but after taking the vehicle to the local dealer no cause of the failure was found. The failure mileage was 110,653.
The contact owns a 2018 Chevrolet Malibu. The contact stated that while driving at an undisclosed speed, the vehicle lost motive power with the traction control and check engine warning lights illuminated. The vehicle was taken to an independent mechanic who diagnosed that the accelerator pedal position assembly needed to be replaced. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was 72,721.
What component or system failed or malfunctioned, and is it available for inspection upon request? A defect in the cam shaft solenoids causes a notice that "Engine Power is Reduced." At that point, the engine begins to struggle to accelerate from a stop, and from increasing speed while on the highway. How was your safety or the safety of others put at risk? The unpredictability of the defect and its affect while driving poses a large threat to safety, particularly on the highway. Has the problem been reproduced or confirmed by a dealer or independent service center? Yes. The dealership service rep not only confirmed the defect, but also confirmed that the issue persists across multiple GM models yet no recall exists. Again, this is a KNOWN defect with GM engines, as confirmed directly by the dealership. …
On Jan 22,2024 while driving on the interstate the speed was unexpectedly instantly reduced, the car would not accelerate over 60 mph and the service engine light came on, the car was safely driven off the highway then towed to the dealership. My safety as well as the safety of other drivers on the highway was at risk when the car suddenly decreased to 60 mph from 75 mph which could have caused a collision. The inspection at the dealership confirmed that the issue was the intercooler for turbo found moisture/oil frozen in charge air cooler causing restriction in induction system, and the part design has been updated to help prevent the issue from happening again. My issue is that if the part has been updated that means that GM is aware of the issue and should be responsible for the cost of the part or there should have been a recall on the part. …
Every so often I get an indication of engine power reduced, but every time I go in to get it checked it's off. I have recently just learned through research online that the issue is caused by a certain condition that gives false reading to the electronics. I have contacted GM and GM financial about the recalls on my cars of the same year. I have not been in a wreck but I have had the issue of engine reduced power in the middle of traffic. Cox Chevrolet in Bradenton has turn me away about the issue GM financial is giving me the runaround neither one mention anything about a recall instead I get a estimate $400 /$808.50/1900.41 all to fix ECM as I told the mechanic I was driving with no problem through the day me and the kids at the park when it was time to leave the car sounded like it just didn't have no gas. We was stuck tell 10:45 we waited two hours for the tow truck. …
After diagnostic troubleshooting from DTCs on a check engine light, it was discovered that the brake vacuum pump connected to the engine was completely nonfunctional. Previous symptoms included stiff brake, loss of brake power at random brake periods which could have cause and accident with other drivers, and finally malfunctioning sensors attributed to the exhaust system. This also led the vehicle to be unable to pass state regulated Emissions testing because of the inability to maintain proper emissions levels. Brake Vacuum pump that was removed from vehicle to inspect and diagnose is still available for inspection. Recent findings show that Chevrolet/GM is aware of the issue in their vehicles but refuses to address or replace faulty brake vacuum pumps. It is a common problem amongst 2013-2022 Chevrolet Malibus. …
As I was driving down the highway at 60 mph the road was clear at the time of any debris my car suddenly had two lights on the dashboard. On the left was the traction control light and the right side was the engine light. On my computer display was the words "reduced engine speed". My car suddenly slowed from 60 to about 30 mph in a matter of seconds. It was like I had slammed my brakes. This all happened simultaneously I attempted to pull over safety and turn the car off and restart it. The lights remained on. My car was not able to get over 27 mph There was no warning what so ever If anyone would have been behind me I would have been rear ended At this time I took it to a mechanic who put it on the computer it was coded at the pedal position sensor. …
Purchase car in December 2018, had 3 engine replacement. I am currently in the 3 engine replacement. And still experiencing the same issue - check engine light permanently on for 2 months now. Issues A whistling sound from an opening vent in the hood since last engine replaced. Call stalls, reduces speed and jerk when trying to accelerate . Have reached out to Reed lallier Chevrolet they making it seems that normal and ok. I am scared to drive and cause an accident because the car stalls before picking up. When you put the car in park, the car still not registering at park it is still moving you have to sit and clear the dash board (shift to park, even thou it is in park). Chevrolet only gave 1 engine replacement and $100 gift card. Every other expense is on me, when I still have to pay for the lemon. Unable to locate most recent engine replacement sheet. …
Acceleration complaints in other Malibu years
Frequently asked questions
How common are acceleration problems on the 2018 Chevrolet Malibu?
NHTSA has 114 complaints about the speed control & acceleration of the 2018 Chevrolet Malibu, 16% of the model year's 700 complaints. The component named most often is accelerator pedal (1 mentions).
Is there a recall for 2018 Chevrolet Malibu acceleration problems?
No. NHTSA lists no speed control & acceleration recall for the 2018 Chevrolet Malibu, though it has 6 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2018 Chevrolet Malibu acceleration problems start?
Half of the complaints with a recorded mileage happened before about 52,000 miles, and 22% before 25,000 miles.
Is it dangerous?
Owners linked 3 crashes, 0 fires and 2 injuries to speed control & acceleration problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.