2018 Chevrolet Malibu Problems

What owners report

Owners of this model year most often describe a sudden loss of power while driving, signaled by an "Engine Power Reduced" message on the dash and sometimes accompanied by stalling and the loss of power steering or brakes. A second common theme is a "Shift to Park" warning that appears even when the car is in park, which can prevent the vehicle from shutting off and the doors from locking. Reports span from very low mileage to well over 100,000 miles, and many owners say the condition came on without warning at highway speed.

1. 1
   Engine

   Reduced engine power / limp mode while driving

   • 303 complaints (43%)
   • median 51,000 mi at 2.9 yrs old (145 state mileage)
   • 9 mention a crash, fire or injury
   • owner-quoted repair $800 (median of 9 quotes)
   • filed 2018–2026

   Owners describe the dash displaying "Engine Power Reduced" and the check engine or traction control light coming on, after which the car will not accelerate past roughly 25-30 mph. Several say it happened at highway speed with traffic behind them, and some report the vehicle stalling entirely with power steering and brake assist lost. Drivers often pull over and restart the car to clear the message, and some were told by shops that the accelerator pedal position sensor, a sensor, or the ECM needed attention. Reported from a few thousand miles up to about 110,000 miles, often at highway speed and without prior warning.

   Recall 19V6420001 related service bulletin

   What to check: Ask whether the ECM software recall (19V642000) was completed and whether any accelerator pedal or ECM work has been done. During a test drive, watch for the check engine light and confirm the car accelerates normally under load.

   2 excerpts from owner complaints in NHTSA records

   “I was driving the vehicle and all of a sudden the check engine light came on and the display read engine power reduced. I wasn't sure what that meant so I pulled over. I tried to pull off and I had no brakes. Apparently something in the braking system broke and my engine was destroyed. I talked with GM and they told me that it has happened before with this model car.”

   NHTSA complaint #11353134, filed 2020-09, 77,000 miles

   “My car reduced its engine power and slowed down from 60 miles down to 20 miles while driving on the high way with a tank truck behind me. I have never been so scared in my life. The engine reduced its power three times now! I was told there was a recall on this and the issue was fixed but clearly it wasn't! I have children and I am terrified to drive my car now because of this!!!!!”

   NHTSA complaint #11319284, filed 2020-03, 52,000 miles
2. 2
   Electrical system

   "Shift to Park" message when already in park

   • 230 complaints (33%)
   • median 40,350 mi at 3.0 yrs old (86 state mileage)
   • 7 mention a crash, fire or injury
   • owner-quoted repair $509 (median of 8 quotes)
   • filed 2018–2026

   Complaints describe a "Shift to Park" warning appearing after the shifter is placed in park, which can leave the vehicle unable to fully shut off and the doors unable to lock. Owners try cycling through the gears or jiggling the shifter repeatedly, sometimes for many minutes, before the car will turn off. Some were told by a dealer that it was a glitch, that there were no open recalls, or that a shifter cable needed replacement. Reported from around 21,000 miles into the 100,000s, and often becomes more frequent the longer it goes on.

   What to check: Before buying, park the car and confirm the instrument panel goes fully off and the doors lock. Ask a seller whether the shifter assembly or shifter cable has been replaced.

   2 excerpts from owner complaints in NHTSA records

   “When placing my car in park, a warning comes on that my car is not in park which then causes me to be unable to turn the vehicle off. I then have to go through each gear and jiggle the shifter numerous times to get it to turn off the vehicle. This sometimes takes up to a half hour of sitting in my vehicle doing that. It is becoming more and more frequent, to the point it is several times a day now. …”

   NHTSA complaint #11364907, filed 2020-10, 43,300 miles

   “The car says it's not in park when you shut it off. The fob seems to not respond sometimes. Sometimes it won't start and tells you to put it into the center console pocket but it still won't respond. It will say there is no fob in the car. I replaced the battery to make sure that wasn't the issue. Even with the fob in the car, it set off the alarm when I tried to start it. It took almost 5 minutes for it to respond to shut the alarm off but it would let me lock the doors while sitting inside it. …”

   NHTSA complaint #11384569, filed 2020-12, 60,000 miles
3. 3
   Electrical system

   Stalling and no-start electrical faults

   • 209 complaints (30%)
   • median 38,467 mi at 2.7 yrs old (98 state mileage)
   • 7 mention a crash, fire or injury
   • owner-quoted repair $1,300 (median of 5 quotes)
   • filed 2018–2026

   Owners describe the car shutting off completely in traffic, at stop lights, or while driving, in some cases with no restart until it was jump-started. Others report the push-button start failing or the car not recognizing the key fob and going into a theft mode. Dealers reportedly diagnosed ECM, accelerator pedal, or battery sensor issues in some of these cases. Reported across a wide range, from near-new to about 100,000 miles, with several cases described as intermittent and worsening.

   1 related service bulletin

   What to check: Check that the car starts reliably from cold and after sitting, and ask whether the battery, battery sensor, or ECM have been replaced. A scan tool check for stored electrical codes is worthwhile.

   2 excerpts from owner complaints in NHTSA records

   “Car turned off in the middle of the road. Engine was completely off as well as no lights were on. So I could not put it on neutral to push it out of the road. I had several near misses where it could have gone badly. Also, took it to the dealership and nothing was found. Car still turns off for no apparent reason”

   NHTSA complaint #11338289, filed 2020-07, 78,000 miles

   “On december 2, 2020 at approximately 545pm I was leaving the biloxi cspire store and as I drove about half a mile, the car completely went haywire. All the instruments went crazy and then I had no brakes at all and the car had no power.. I was barely able to get the car in a safe spot and myself out of danger sitting in the middle of a busy road. I tried to turn and get off road and car had no brakes at all and no power. Then once I was able to get in a parking lot the car and safe. …”

   NHTSA complaint #11383971, filed 2020-12, 83,000 miles
4. 4
   Steering

   Steering assist reduced warning

   • 44 complaints (6%)
   • median 50,000 mi at 3.0 yrs old (20 state mileage)
   • 2 mention a crash, fire or injury
   • filed 2018–2026

   Owners describe a "Steering Assist Reduced" message flashing on the dash, sometimes with a brief pull to one side of the wheel, usually at low speed or right after restarting the car. Several say the dealer found nothing wrong when the vehicle was inspected. Reported mostly at low mileage, often in stop-and-go traffic or right after starting the car.

   What to check: During a slow-speed test drive, watch for the steering warning and any pull in the wheel at startup; ask whether the steering assist has been inspected or any codes stored.

   2 excerpts from owner complaints in NHTSA records

   “I was driving in a neighborhood about 15 MPH. My car began to shake, the engine light was blinking, stability track light was on, and an icon came up saying that the 'service stablitrek.' I had little control over the steering and I felt no traction while trying to pull over. I also have a problem where the car prompts a shift to park, even though my car is in park.”

   NHTSA complaint #11364304, filed 2020-10, 50,000 miles

   “I was driving my car this morning this happened 4 times, I was in a stop when I would restart the car to go my steering wheel would do a quick shift to the left then back to its original position then I would get the steering assist reduced sign for second then disappear. It did it 4 times in a matter of an hour and a half. And did it once last week with no massage display.”

   NHTSA complaint #11373860, filed 2020-11, 62,000 miles

Buying note. These are mostly electronics and powertrain control complaints rather than wear items, so a scan-tool check for stored codes, confirmation that the ECM recall was applied, and a careful low-speed and highway test drive are the most useful steps before buying.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.