Chevrolet Blazer owners have reported 200 problems related to engine and engine cooling (under the engine and engine cooling category). The most recently reported issues are listed below. Also please check out the statistics and reliability analysis of Chevrolet Blazer based on all problems reported for the Blazer.
I received a check engine light which I took to bell tire for diagnosis. Here is there diagnosis comments: the p01f0 code on a 2020 chevy Blazer means the engine coolant temperature is below the normal operating range, often due to a stuck-open thermostat (or both thermostats in models with dual units), a faulty engine coolant temperature (ect) sensor, or low coolant, leading to poor fuel economy and potential wear; fixing it usually involves replacing the thermostat(s) or sensor after checking coolant levels and wiring. After that I took the vehicle to gm dealership. Even though this is a know issue with many vehicles from same year, I was told that my VIN is not part of recall and dealership ended up charging me 600+ to fix the issue. I am reaching out to seek help as I had exact same problem but gm is not covering the repairs because my VIN is not in the recall. How is that possible?.
See
all problems of the 2020 Chevrolet Blazer
🔎.
I bought this car brand new. 0 miles. I’ve had an oil leak fixed once in it. And now it’s leaking oil again. I have to have it put back in the shop and pay out of pocket once again for now fault of mine. The first time it was leaking from the cam shaft. This is ridiculous. I will also be filing a complaint with chevy.
The engine started acting weird in traffic going down hill on freeway. Eventually turned off turning into my driveway. No warning or engine light. Towed to dealer and is in for inspection, not sure if they can repair or if they have to replace the engine. When it arrived to dealer the engine light was on with a couple misfires.
See
all problems of the 2025 Chevrolet Blazer
🔎.
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. ?.
See
all problems of the 2021 Chevrolet Blazer
🔎.
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.
Engine showing po128 code. Steering assist system reduced power. Engine fan constantly running. Engine temp on dash is stuck on the "c" mark, doesn't move. Thermostat and temp sensor replaced, issue continues. This is a very common problem on gm vehicles with the 3. 6l around the 60,000 mile mark. Gm needs to get it figured out.
For about a week and a half my car had made a high pitched wheezing/hubbing sound when started cold. This occurred at all temperatures cold and warm. Yesterday December 13th I went to run some errands and about a mile into my drive my 2021 3lt 3. 6 v6 Chevrolet Blazer lost the ability to power itself. There was no electrical problem however the power train lost power all gears drive and reverse. I was able to get off the roadway without incident. I scan my check engine light and had several check engine lights including a p 0796.
2020 Blazer, 65,000 miles. Temp stuck on cold, a/c blows warm aor and driving assistance off. The radiator fan runs continuously. Check engine light on.
Thermostat/thermostat sensor and complete water outlet system replacement at only 52,377 miles. The defective part was located under the intake manifold requiring its removal, excessive labor cost for the repair, and potential future engine issues due to exposed/open head gasket for the repair.
My 2021 Chevrolet Blazer experienced a radiator failure at approximately 42,000 miles. The radiator and cooling system malfunctioned, causing coolant loss and triggering a warning light on the instrument panel. The failed radiator is available for inspection upon request. This defect put my safety and the safety of others at risk because a compromised radiator can lead to engine overheating, sudden loss of power, or even steering assist reduction while driving. These conditions increase the likelihood of an accident, particularly at highway speeds. The problem was confirmed by my Chevrolet dealer, who diagnosed the radiator as needing replacement. They initially quoted $1,800, later reducing the cost to $915. 90 after acknowledging that approximately 20 customers per month at their dealership alone are experiencing the same issue. This indicates the defect is widespread, at least regionally, and may be systemic across the model. The vehicle has been inspected by the dealer service department, which is an authorized gm representative. No police or insurance inspection has occurred. Prior to the failure, a warning lamp illuminated on the instrument panel, alerting me to a cooling system issue. This was the first symptom I noticed before bringing the vehicle in for service. I believe this premature radiator failure represents a systemic defect in the 2021 Chevrolet Blazer’s cooling system. It occurred well within the 5?year/60,000?mile warranty period, yet the dealer claimed the radiator is not covered. I am requesting NHTSA investigate this issue, as it appears to affect many owners and poses a significant safety risk.
Car was running fine yesterday, today does not want to start. Thought it was the battery, bought anew battery. Still wouldn't start. Rest of cat is getting great power. Code reader is reading its a fuel pump control moduler which just so happens to be in an open recall for my exact year of vehicle yet my VIN number does not pop up on the GMC website under active recall. I have a 2021 chevy Blazer .
In September 2023, when getting my vehicle serviced for a routine oil change, I was told there was a leak in my radiator. They replaced the entire thing under warranty. On November 15th, 2025, while driving on the highway heading home from out of town with my children, an error flashed up saying “steering assist is reduced – drive with care” upon arriving home, the fan on my car was running on high for a solid 10 minutes after turning the car off. No recall but special coverage n252508350 covers the thermostat replacement. Upon inspection by a mechanic, I was informed that the radiator is also leaking again in the exact same spot as it was previously. It should be noted I have never seen leaking fluid in my garage/driveway. I’ve driven less than 10,000 miles since the radiator was replaced previously. If there is a known problem with the coolant system which can cause overheating and steering assist issues, why isn't the faulty radiator and thermostat recalled. The radiator is cased in plastic to aluminum. Plastic can easily catch fire if a car overheats. The casing also prevents an owner from even knowing if there is a leak since the plastic is catching leaks - the mechanic informed me that's why I didn't know about both times it leaked. This is a 4yr old car with 46k miles, twice replaced radiator and thermostat. A recall should be issued since both problems could potentially cause a fire from an overheated engine & loss of steering assist while driving. A google search quickly showed me thousands of other chevy Blazers from 2019-2021 with reoccurring thermostat and radiator issues. I feel unsafe driving in my vehicle but still owe too much to even trade it in for something else. I've owned dozens of vehicles in my lifetime, used and new and keep them 8-10yrs and have never had to replace a thermostat and radiator. This vehicle is dangerous due to gm/chevy's cheap radiator model and thermostat which could overheat and catch fire.
The radiator developed a leak at around 36k miles and needed to be replaced. My understanding is that this is an ongoing problem with this vehicle.
See
all problems of the 2023 Chevrolet Blazer
🔎.
We are noticing the coolant meter seems to be stuck on c, the ac is not blowing cold and we are getting a message that action required steering assist is reduced, drive with caution. Today the brakes slammed on by themselves and almost sent my wife thru the windshield. Luckily she was in a clear area with no other cars around.
See
all problems of the 2019 Chevrolet Blazer
🔎.
Car is displaying a “steering assist is reduced drive with caution” engine light is on and fan continues to run for 5-8 minutes after car is turned off. Was told by a mechanic it is a p0128 code, coolant thermostat. This is the third time it has happened in the last year. Other two times the codes cleared.
See
all problems of the 2022 Chevrolet Blazer
🔎.
Radiator failure caused power steering assist to not function properly and insufficient vehicle heat function. Engine electric fan would run continuously after vehicle shutdown.
Put my car into park and the fan kept running continuously. I noticed that the engine temperature gauge did not move off of cool either. When I drove it, I got an alert that the ‘steering assist was reduced’ and shortly after my check engine light came on. My safety was at risk due to the fact that I couldn’t monitor my engines temperature and it very well could have been overheating and I would’ve never known. I took it to the dealer and they did confirm that my thermostat was stuck open and wasnt allowing my engine to get up to temperature. My ecm module had to be replaced as well. The mechanic said, had it closed my engine would’ve overheated with no signs until it was too late.
Engine temperature gauge is not working. Dash is displaying driver assist issue and steering intermittently locks up while moving. Air conditioning does not work and cooling fan is running at high speed. Thermostat and coolant temperature sensor need to be replaced. Such a high number of these vehicles are failing that I can’t even get factory parts.
"steering assist reduced” warning message appears on dashboard display and temperature gauge stuck on cold on the dashboard display. I understand this such a common issue with the 2019 and 2020 Blazer that general motors has issued technical service bulletins but refuses to repair these vehicles for free. This is unacceptable! issue a mandatory recall therefore gm must perform the repairs for free.
The thermostat failed on a trip locking in 0 temperature reading and steering assist warning. Licensed mechanic repaired on 10/9/25 invoice is available. 67,509 miles. This could risk overheating and destroying the engine and might cause accident. Two other friends have had similar issues, appears to be a safety defect!.
Engine light on, power steering assist, air conditioning stop working diagnostic tool read p0128 coolant thermostat.
Dashboard goes on like a christmas tree (almost all lights turn on abs gas light traction control parking service light) check engine stays on then disappears after a few days. Transmission won’t gear into shifts only stays in one shift.
Was informed at today's oil change that my radiator is leaking and it's something that they are seeing a bunch.
Action required "steering assist warning" drive with caution, temp gage reads cold, a/c stops working, engine cooling fan runs on high speed (even after the engine is shut off), pending p2018 code, with no check engine light (cel). Replaced engine coolant temperature (ect) sensor, problem did not go away. Several reviews suggest to replace the thermostat, check fuses for proper insertion, reroute ect wiring, and possibly replace radiator. Most of these repairs can be very expensive. Chevy Blazer forum states that the issue is a out of range detection of ect sensor reading. Gm needs to determine a true solution and stop guessing at owner expense/frustration.
Check engine light on, message saying "steering assist reduced drive with care", engine temperature gauge not moving from c, and ac not working. I have taken it in to be fixed 3x, and they have fixed it 2/3 times but the message has come back again. It is a big issue in 2019/2020 Blazers according to my research.
Thermostat not working. Causing fan to run as if the vehicle is overheating.
Transmission & engine failure. Press the gas and it doesn’t move the car-feels as if it is trying to change gears and it isn’t working. Car under warranty & still not working. Been to the dealership multiple times and they are unable to fix the issue. No warning signs.
See
all problems of the 2024 Chevrolet Blazer
🔎.
Thermostat has gone bad. Talked to chevy and they said it is a known issue.
My vehicle lost complete power while I was sitting at red light. The dashboard went completely out and pop back on stating to put the vehicle in park and push the brake to start. After following those instructions the vehicle failed to start and I left disability until onstar notified mpd to assist. While waiting for assistance I was almost hit 3 times. When mpd arrived on the scene they were able to push the vehicle out of traffic. After my vehicle arrived at the shop I was told the power failure was caused by the malfunction of the DC/DC converter output voltage. I see a bulletin was put out but a recall was my made available. I feel this is a major issue due to the vehicle losing power.
The thermostat has been sticking, and needs to be replaced after only 30,000 miles.
P0128 code for thermostat issue. Fans run after shutting car off. Steering assist reduced message. Check engine light. Chevy knows this is a common issue. This needs to be investigated ASAP.
2020 Chevrolet Blazer, 19900 miles, lightly driven the radiator seam is leaking coolant, which appears to be a known issue as there are numerous complaints on various websites and forums. The vehicle is now unreliable due to an overheating risk.
I am writing to inform the appropriate authorities of the issues that I’ve continually had with my 2023 Chevrolet Blazer. It has come to my attention that the aforementioned vehicle will need a new transmission and possible engine repair currently totaling at just over 6,000 dollars in repair costs. When I was provided with the total repair cost I was informed by the certified service representative that this was a common issue for the Blazer model and that gm was aware of the ongoing issue. I’ve reached out to gm with my concerns regarding this vehicle and the fact that this is an issue that has in prior dates prompted recalls for Blazer models from the year 2020-2024. I have because of the transmission defects/ failures been stranded and unable to shift gears required for proper motion of the car. To which I am sure you can understand the public safety risk of an inoperative transmission. I have taken the car in for service concerning the transmission on 3 separate occasions within the last 10 days and was told by prior service technicians that “ no problems were visible” leading to the total breakdown of the transmission. I reached out to gm and told them of my wish to return the leased vehicle early due to my fears of now driving and operating the car and was told that I was not eligible for a buy back. Gm is maintaining its stance of no liability and I am seeking outside help from this governing agency to ensure that repair costs are fully covered for this defective product.
Was getting a steering assist reduced error code. Auto stop quit functioning and air conditioning stopped cooling. Engine sounded like a jet. P 0128 thermostat error code came up and had to be replaced. I see lots of similar complaints. Cost me $700.
At routine oil change dealer noticed radiator was leaking. 60,840 miles took it to an independent repair shop who confirmed radiator needed to be replaced. Has also seen same on other 2021 Blazers. No visible signs of leaking (fluid on garage floor) or warning indicators. No recall issued on this, however, seems to be a common problem on 2021 Blazer based on chevy forums. Due to safety issues, vehicle is currently in shop for the needed replacement repair.