RoadVitals

2021 Chevrolet Blazer Owner Complaints

Reports submitted to NHTSA by owners and drivers, shown in full

Data refreshed

Complaints on fileComplaints are reports submitted to NHTSA by owners and drivers. NHTSA does not verify most reports before publishing them, and a complaint does not establish that a defect exists. Volume is influenced by how many of a vehicle were sold, how long it has been on the road, and how much attention an issue has received.
125
+2 complaints in 30 days
Crash or fire reportedComplaints whose submitter recorded that a crash or a fire occurred. These are the reporter's own answers on the NHTSA form, not verified findings.
7
Filed in the last 12 monthsReports filed with NHTSA in the trailing 365 days. Recent volume reflects attention and vehicle age as much as anything else.
49
Reports on file since Mar 15, 2021

What this page shows

Our database holds 125 NHTSA owner-reported complaints for the 2021 Chevrolet Blazer. Each one is a report filed by an owner or driver and published by NHTSA without most of them being verified. A complaint is not a confirmed defect, not a recall and not a manufacturer bulletin. Narratives are shown exactly as filed.

Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.

Complaints, most recent first

Showing 1–25 of 125 · page 1 of 5

Airbags
Filed Jul 30, 2026
Crash reported1 injury reported

The contact owns a 2021 Chevrolet Blazer. The contact stated that while driving at approximately 50 MPH, the vehicle struck a deer, causing severe damage to the vehicle's front end. The contact stated that smoke was coming from the center of the steering wheel; however, the vehicle's air bags had not deployed. The contact was transported to the local hospital and treated for chest injuries. The vehicle was towed to a local collision center. No further information was available. A Police report was filed at the scene. The cause of the failure was not yet determined. The local dealer and manufacturer were not yet contacted. The failure mileage was 52,661.

NHTSA ID
11753752
Incident
Jul 29, 2026
Mileage
52,661 mi
Powertrain (other)
Filed Jul 21, 2026

The contact owns a 2021 Chevrolet Blazer. The contact stated that while driving at an undisclosed speed, the accelerator pedal was depressed, and the transmission was slipping gears before the vehicle lost motive power. The contact stated that the vehicle failed to drive forward or move while in reverse. The check engine warning light was illuminated. The vehicle was towed to the residence. The contact, who was an independent mechanic, diagnosed the failure as a clutch solenoid failure. The contact stated that the transmission needed to be replaced. The vehicle was not repaired. The contact referenced an unknown recall; however, the VIN was not associated with a recall related to the failure. The dealer was made aware of the failure but provided no assistance. The manufacturer was made aware of the failure but provided no assistance. The failure mileage was approximately 100,000.

NHTSA ID
11751752
Incident
Jul 16, 2026
Mileage
100,000 mi
Fuel system
Filed Jul 9, 2026

fuel pump control module failed at 26000. recall number N252516900. This is a recall that other 2021 blazers have ben part of. Over 300000 recalls so far. GM says my car isn't. Ridiculous. They dont want to acknowledge their fault. I need a formal statement that this module should be recalled for my car.

NHTSA ID
11749371
Incident
Jul 4, 2026
Fuel system
Filed Jul 9, 2026

XXX the car had gas, turned over, but would not start. I had it towed to a repair center who towed, did diagnostics and came up with the codes for a bad fuel pump control module. It was replaced and the car starts. There was no warning. Problem was confirmed by an independent service center. All documentation is available. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID
11749347
Incident
Jul 4, 2026
EnginePowertrain (other)
Filed Jun 23, 2026

The thermostat malfunctioned causing an error message regarding “steering assist is reduced”. When I parked and turned off, the engine fan continued to run. When car was restarted, the temp gauge inside was stuck at C. Took to dealership and they assessed. They repaired the thermostat under power train warranty, however there was a crack in the radiator (top) resulting in the need for a new radiator. This vehicle had 35,000 miles on it. Upon research online, it seems there are MANY people who have had this same issue and worse. It appears cars produced during COVID era are most affected. Chevy refused to warranty the issue. The dealership offered a small cost reduction (due to our loyalty). The thermostat and the radiator issues seem to be well known by Chevy, they just refuse to accept responsibility. Now we are out thousands of dollars on a basically “new” vehicle.

NHTSA ID
11745926
Incident
May 27, 2026
Driver assistanceElectricalEngine
Filed Jun 22, 2026

The thermometer and thermometer sensor are glitching . The engine temp needle will not rise at all, the engine fan will run the whole time driving and then when it is turned off will run for 10 min . Right before this happens a notice shows the guided steering is being limited. I disconnected the battery and it reset , I drove and there were no issues , next time I started my car the engine temp needle stayed down and the van started again. This car has 36k miles on it. I just bought it 2 days before it started happening

NHTSA ID
11745573
Incident
Jun 21, 2026
Electrical
Filed Jun 6, 2026

Lost coolant temp so replaced sensor with one from auto zone and worked for one then pegged to cold again fan runs 100% so went and bought another coolant temp sensor from Chevrolet installed that worked two pegged back to cold again fan 100% now going to pay $700.00 dollars to remove the two sensor wires for the harness all the two the Ecm heard with it being wrapped in the coil wires it gets electromagnetic static due to degradation of wires. Also Radiator started leaking after couple years but they want $3100.00 dollars for that.Was told extended warranty ran out three days before they discovered radiator leak.

NHTSA ID
11742425
Incident
May 6, 2026
Steering
Filed May 19, 2026

The vehicle showed an error on the dash which stated "Action Required Steering Assist is Reduced Drive with Care" I tool the vehicle to the dealer I purchased it from McClusky Chevy at Kings Auto Mall in Mason Ohio. They informed me that the error code is C0460:58 and GM has a service bulletin 20-NA-215 which advises to replace the Steering Gear due to internal component interference. No one explained to me that this could cause catastrophic failure and lead to a crash before I left the dealership. They could not replace it as they said they do not have the part and it is on national backorder. Additionally they told me the repair would cost me $3,400. The vehicle has 42k miles on it and this repair is not under warranty as the warranty that would have covered it expired in March of 2026. I have taken the vehicle to a different GM dealer - Tom Gill GMC in Fairfield Ohio - they are waiting on the part and I have a case opened with GM regarding the costs. You would think that if there is a risk of a catastrophic failure which could cause harm to my self or someone else - the dealer would have an obligation to tell me so before i drive off. If not legally, certainly morally.

NHTSA ID
11738765
Incident
May 4, 2026
Suspension
Filed May 12, 2026
Crash reported3 injuries reported

Driving on straight road going speed limit. Heard a pop behind me like a tire pop. Car fish tailed uncontrollably and ended up crashing into a Ranch Fence on the right side of the road. 2 of my kids and myself had injuries. When we got off the vehicle witnesses and I saw A rear link broken which keeps the tires straight.

NHTSA ID
11737304
Incident
May 11, 2026
Fuel system
Filed May 1, 2026

I am reaching out regarding an ongoing issue with my 2021 Chevrolet Blazer. The vehicle is experiencing a noticeable stutter or hesitation when shifting between second and third gear. In addition, there are instances where the vehicle accelerates unexpectedly or more aggressively than intended. This behavior is particularly concerning, as it presents a potential safety issue during normal driving conditions. These concerns have become increasingly noticeable, and I am concerned they may indicate a transmission or related mechanical problem that requires prompt inspection and resolution. Please advise if there are any known service bulletins, recalls, or warranty coverage related to these issues. For reference, the vehicle has been properly maintained and this behavior is not consistent with normal operation. Given that this is now the third major issue I’ve experienced with this vehicle, I am hoping this matter can be addressed without additional out-of-pocket expense. After additional research, I have learned that other owners have experienced the same issue. Others have stated the following: 1. Hesitation, stuttering, or jerking between gears Owners of 2020–2021 Blazers report hesitation and jerking during acceleration, sometimes described as gears “shifting in and out rapidly.” Forum users mention sluggish shifting or slipping feelings, especially at certain speeds. Others report hard or delayed shifts at low speeds (like 15–25 mph). 2. Shuddering / vibration (often tied to torque converter) There are repeated mentions of “shudder,” “surge,” or vibration during acceleration. Some cases were linked to: Contaminated transmission fluid Torque converter clutch (TCC) issues One owner said the problem felt like a bad torque converter and required service attention. 3. Unexpected acceleration / lunging Drivers across GM vehicles (including similar transmissions) report: “Jerking,” “bucking,” or “lunging” during acceleration Some describe needing to

NHTSA ID
11735127
Incident
Sep 1, 2025
BrakesEngineFuel system
Filed Apr 29, 2026

Went to park car in a park to drop daughter off and it sputtered out and stalled out of nowhere with no warning. I had received a lamp warning very sporadically prior to this and on occasion that stated 'reduced steering assist drive with care' this resulted in heavy steering for that drive until car was shut off and then it would go away and be fine again, fixed the car through Knudtsen Chevy due to a recall about a month before on the issue with the engine being turned off and it thinking it was still hot and still running the fan (even though the car was not running). Knudtsen fixed that issue. Low battery voltage light did not come on however battery was older so had battery installed at park to ensure the issue was not due to the battery. The oil was fresh and showed no issues, changed 2 weeks before fresh oil no issues found during service. When tried to restart the car it would think it would try to start and then sputter out and not stay in idle. Les Schwab left and called a mobile mechanic to bring the computer. Computer was hooked up and it would try to start, however, it would not know it was already running and try to start again on it's own...the codes that came up were the PO101 code came up for Mass Air Flow issue...and then the codes would go in a wild sequence of fail.....mechanic checked for loose connections around air filter, took air filter out and it was clean no issues, checked pipe no visible issues. We walked away and walked around the park to give it some time to sit and then we tried it again and it tried and sputtered out and died again would not stay idling. Then all of a sudden we heard it try to start itself without us trying to start it and it clanked. We hauled it to Knudtsen for a diagnosis. They stated "the motor will not turn this way or that way and it is seized or locked up". This is a 2021 with only 89,000 miles it should have a longer life than this. Please investigate and is there anything we can do to fix it?

NHTSA ID
11734510
Incident
Apr 18, 2026
Engine
Filed Apr 28, 2026

Both camshaft carriers failed due to a manufacturing defect. According to NHTSA bulletins 21-NA-240 and PIP5755, the oil leak from the cam carrier is caused by improper sealant application during manufacturing. Although the dealer addressed the issue, it was clearly not a problem that arose from normal use. The leak had the potential to worsen and lead to a fire hazard. Chevy of Montebello confirmed the issue and repaired the vehicle for over $7,500. There were no warning signs, as the leak was difficult to detect on the driveway. The low-oil warning light came on the day before we took the vehicle to the dealer.

NHTSA ID
11734437
Incident
Apr 1, 2026
Powertrain (other)
Filed Apr 23, 2026

The transmission (powertrain) developed a delay when shifting into reverse, followed by harsh engagement. The condition worsened over time and resulted in a complete loss of reverse. The vehicle will not move when shifted into reverse. This creates a safety risk when parking, backing out of spaces, or maneuvering in traffic, as the driver cannot safely control vehicle movement. The issue occurred at approximately 89,000 miles under normal driving conditions. No warning lights were present prior to failure. The problem was reported to a dealership and diagnosed as a transmission failure. The condition is reproducible and ongoing. I was also informed that multiple vehicles of the same model were experiencing similar transmission issues at the same time. The failure limits safe operation of the vehicle and increases risk in situations where reverse movement is required.

NHTSA ID
11733441
Incident
Apr 23, 2026
Brakes
Filed Apr 22, 2026

The contact owns a 2021 Chevrolet Blazer. The contact stated that while driving at an undisclosed speed, there was an abnormal sound coming from the vehicle with several unknown warning lights illuminated. The contact stated that the electronic parking brake independently activated. Additionally, the failure had occurred while the vehicle was parked. The failure was persistent. The vehicle was not diagnosed or repaired by an independent mechanic or a dealer. The manufacturer was not made aware of the failure. The failure mileage was approximately 31,000.

NHTSA ID
11732946
Incident
Feb 18, 2026
Mileage
31,000 mi
Engine
Filed Apr 16, 2026

The vehicle had an oil leak from both the left and right camshaft carriers. The dealer confirmed the issue and carried out the necessary repairs. Because the leak was not easily detectable, it could have led to engine failure while driving. There were no warning indicators; only small oil droplets were found on the ground.

NHTSA ID
11731606
Incident
Apr 7, 2026
ElectricalEnginePowertrain (other)
Filed Apr 12, 2026

Once I turn the vehicle off, there is a loud sound coming from the engine area that sounds like a fan. Then the first incident of the fan ongoing after the vehicle was powered off, a battery light was on the internal driver dashboard and stayed on. The battery was recently replaced during 2026 so the battery should not be anywhere near dead, dying, or needing to be checked

NHTSA ID
11730609
Incident
Apr 11, 2026
Electrical
Filed Mar 25, 2026

The contact owns a 2021 Chevrolet Blazer. The contact stated that while attempting to start the vehicle, several unknown warning lights illuminated, and other lights inside the vehicle flashed on and off. The contact stated that the failure also occurred while driving at various speeds. A dealer was contacted. The vehicle was taken to several dealers for diagnostic tests; however, the diagnostic result was unknown. The manufacturer was notified of the failure and informed the contact that there would be a callback about the cause of the failure; however, there has been no callback yet. The approximate failure mileage was 50,000.

NHTSA ID
11726942
Incident
Aug 15, 2025
Mileage
50,000 mi
Engine
Filed Mar 12, 2026

Coolant smell when parked with engine running. Radiator was replaced under warranty at ~16,000 miles Coolant smell again ~49,000 miles. "Pressure tested at dealership with following notes: "Found radiator core on driver side seeping/leaking. provided estimate on cost. no repair made during this visit." Many forums on 2021 Chevrolet Blazer note poor quality in radiators. This would be the 3rd radiator in less than 50,000 miles on the vehicle.

NHTSA ID
11723904
Incident
Jul 24, 2025
Powertrain (other)
Filed Mar 12, 2026

My 2021 Chevy blazer Lt v6, has a service bulletin extending warranty on thermostat malfunction, that also causes the fans to run after the car is off. My vechicle was experiencing this issue, went into my local dealer, they claim thats not my issue, I need a new radiator, that has never leaked, or the car running hot. Beyond that the radiator has a service bulletin, they can fail, do to poor quality from supplier, some were replaced under warranty, some were not. This vechicle has 47000 miles, I should not be responsible for this issue. Thank you [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID
11723823
Incident
Mar 9, 2026
Filed Mar 3, 2026

At 48,000 miles, check engine light came on and loud fan sound continued after turning car off. Took car to dealership where I was informed I needed a new radiator and it is not covered by warranty.

NHTSA ID
11721657
Incident
Feb 19, 2026
ElectricalEnginePowertrain (other)
Filed Feb 19, 2026

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. Since filing my original complaint, I have identified multiple similar reports online and in owner forums describing premature throttle body failures in GM vehicles with similar symptoms (reduced power/limp mode and limited acceleration). This suggests the possibility of a broader pattern involving this component. I am submitting this additional report so that NHTSA has a complete record of the incident and potential pattern of premature throttle body failures. If this issue is widespread, it may warrant further review or investigation as it affects vehicle acceleration and safe operation.

NHTSA ID
11719088
Incident
Jan 7, 2026
Engine
Filed Feb 9, 2026

The 2021 GMC Blazer (and related Chevy Blazer models) is experiencing recurring radiator failures, often requiring multiple replacements within short timeframes. The radiator was replaced in March 2024 and in early 2025 I went for an oil change and complained of smelling coolant and asked if it could be checked and was told nothing was wrong. I was told again in November 2025 that it has a leak and went to have an oil change in February 7, 2026 and was reminded that the coolant was low and the radiator needs replacing when I was first told I did not believe it to be true as it has been replaced before and I asked that it be checked and was told nothing was wrong.

NHTSA ID
11716656
Incident
Feb 7, 2026
ElectricalEnginePowertrain (other)
Filed Jan 30, 2026

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. The component has been replaced and is available for inspection upon request. I believe this may represent a premature defect and should be investigated for similar failures in other vehicles.?

NHTSA ID
11714381
Incident
Jan 7, 2026
Filed Jan 12, 2026

Thermostat issues, gives warning steering assist decreased and then eventually check engine light, vehicle thermostat does not react/reach normal temperature, fan continues to blow after car is turned off for 5-15min, AC does not blow cool air or warm if heat turned up

NHTSA ID
11710504
Incident
Dec 1, 2025
Engine
Filed Dec 29, 2025

Radiator failure caused power steering assist to not function properly and insufficient vehicle heat function. Engine electric fan would run continuously after vehicle shutdown.

NHTSA ID
11707571
Incident
Oct 28, 2025

Higher-selling and older vehicles accumulate more reports. Counts are not failure rates and are not directly comparable between vehicles that sold in very different numbers.

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