Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2021 Chevrolet Blazer owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2021 Chevrolet Blazer. The contact stated that while driving approximately 10 MPH and attempting to make a left turn, the vehicle stalled. The contact depressed the accelerator pedal aggressively several times to get the vehicle to start moving again. The failure reoccurred while the contact's daughter was driving and attempting to make a left turn at a green light when the vehicle stalled. The contact stated that the failure persisted while driving and attempting to turn to the left. The failure occurred intermittently. The contact stated that only the rear tires would move. The contact took the vehicle to the dealer who was unable to find the cause of the failure. The dealer was not able to duplicate the failure. The failure persisted. The manufacturer was made aware of the failure and opened a case. The approximate failure mileage was 28,000.
The contact owns a 2021 Chevrolet Blazer. The contact stated that a technician identified a radiator leak during an emissions test after smelling an abnormal coolant odor. The technician confirmed that the coolant had leaked from the vehicle. Prior to the discovery by the technician, the contact's husband observed white smoke coming from the engine. The fluid levels were checked and were normal at that time despite the smoke. Additionally, the contact stated that the message "Steering Assist Reduced" was displayed on the instrument panel prior to the failure. The vehicle was not repaired. The dealer provided an estimate for the repair with 15% goodwill assistance towards the cost. The manufacturer was notified of the failure. The vehicle was not repaired. The failure mileage was 46,860.
The contact owns a 2021 Chevrolet Blazer. The contact stated that upon turning off the vehicle, the fan remained engaged for approximately 10 minutes. Additionally, the contact stated that the A/C system was intermittently inoperable. The contact stated while driving at an undisclosed speed, the vehicle made an abnormal sound, and the contact noticed that there was a coolant leak onto the floor of the vehicle. An unknown warning light was illuminated. The vehicle was taken to East Houston Auto Electric, where it was diagnosed that the thermostat was stuck and needed to be replaced. The vehicle was not repaired. The dealer and the manufacturer were not notified of the failure. The failure mileage was approximately 95,000.
The contact owns a 2021 Chevrolet Blazer. The contact stated that oil was leaking from the vehicle. There were no warning lights illuminated. The vehicle was taken to the local dealer, where it was diagnosed that the cam shaft carrier needed to be replaced. The vehicle was repaired, but the failure recurred. The vehicle was taken to an independent mechanic, who determined that there was a separation in the transmission, oil cooler line, valve, and hoses that needed to be replaced. The vehicle was not repaired. The manufacturer was contacted and submitted a complaint. The failure mileage was approximately 63,000.
The contact owns a 2021 Chevrolet Blazer. The contact stated that the check engine warning light was illuminated. The contact was unable to use the electrical features in the vehicle. The vehicle was taken to the local dealer, where it was diagnosed that the purge pump needed to be replaced. The vehicle was not repaired. The manufacturer was contacted and opened a case. The approximate failure mileage was 36,000.
I went out to start my car and the light said that it was not reading the key fob because of low battery. I went and got the other key fob which had never been used and had the same result. The car was towed by Chevrolet to the dealer and it has been there for over 3 weeks. They found that it wasn't a faulty key fob but it was the receiver that gets the signal and allows the door locks to open and the engine to start. I tried moving the shift lever, stepping on the brakes, trying the remote start on the key fob and nothing would start the car nor would it lock/unlock the doors. It just kept giving me the notice that it couldn't read the key fob. I called ONSTAR and tried the actions they told me but that did not work either and they said to contact my selling dealer. ONSTAR contacted the Chevy warranty number for a tow truck but at 9PM it was too late for them to make a service call. …
On the way to work my car said "driver assist is stopping drive with care" about 2-3 times. Upon getting out of my car it sounded like my car was still running. I turned it off and on a few times and it still sounded that way. I had to go inside or I would be late so about 20 minutes later I was able to come back and check on it and the noise stopped. It was coming from the hood. Upon googling I figured it was something to do with a faulty temperature gauge which correlated with the signal from the car as well as the sounds. It seemed like this is a very common occurrence for these cars. I called the dealership and they said they fix these everyday and the man knew exactly what was wrong before I could even finish describing it. …
This submission is an additional report related to NHTSA complaint #11714381. At approximately 55,000 miles, my 2021 Chevrolet Blazer experienced a sudden throttle body failure while driving. The vehicle entered reduced engine power/limp mode without warning and acceleration was significantly limited. This created a safety concern while driving in traffic, particularly when merging and crossing intersections. Diagnostic code P2101 (Throttle Actuator Position Performance) was present. A Chevrolet dealer confirmed an internal throttle body failure and replaced the throttle body assembly. Although the repair was completed, this failure occurred at relatively low mileage for a critical engine control component. A sudden loss of acceleration can pose a safety risk depending on traffic conditions. …
Receiving 3 different errors on dash display. 1) Action Required- No Remote Detected 2) Action Required- No Remote Detected Press Brake to Restart 3) No Remote Key Wa Detected Place Key In Transmitter Pocket Then Start Your Vehicle. All of these errors are intermittent and have appeared with using 2 different Remotes. Batteries have been replaced also. This in itself is not so much a safety hazard (annoying), but what is intermittently happening is the car shuts down while in drive and in reverse. So far it has not shut down on the freeway but has shut down while on City streets. We have taken it to 2 different GM Dealers a total of 7 times in the last 3 months(currently at the dealer now). Each time the dealer is saying they cannot duplicate the errors. We get it back and within 1 (usually the same day)day it is right back with the errors. …
Around 55,000 miles, my 2021 Chevrolet Blazer experienced a throttle body failure. The check engine light illuminated and the vehicle entered a reduced power/limp mode condition. Throttle response was significantly limited, and the vehicle could not accelerate normally. While the vehicle remained drivable, it took substantially longer to reach speed, which could pose a safety risk when merging into traffic or crossing intersections. Diagnostic trouble code P2101 (Throttle Actuator Position Performance) was present. A Chevrolet dealer confirmed an internal throttle body failure and replaced the throttle body assembly. This component is a critical engine control system, and failure could affect acceleration and vehicle control, posing a potential safety risk. The failure occurred well before expected service life and required a costly repair. …
Engine complaints in other Blazer years
Frequently asked questions
How common are engine problems on the 2021 Chevrolet Blazer?
NHTSA has 45 complaints about the engine & cooling of the 2021 Chevrolet Blazer, 32% of the model year's 139 complaints. The component named most often is cooling system › fan (1 mentions).
Is there a recall for 2021 Chevrolet Blazer engine problems?
No. NHTSA lists no engine & cooling recall for the 2021 Chevrolet Blazer, though it has 1 recall 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 2021 Chevrolet Blazer engine problems start?
Half of the complaints with a recorded mileage happened before about 47,000 miles.
Is it dangerous?
Owners linked 0 crashes, 1 fire and 0 injuries to engine & cooling 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.