2020 Chevrolet Blazer: engine overheating

Filed Jun 11, 2026 · Transmission · WA

I am submitting this complaint regarding my 2020 Chevrolet Blazer and what appears to be a widespread cooling system defect. My vehicle has developed a coolant smell outside the vehicle, which raises concerns about a coolant leak from the radiator. After researching the issue, I discovered that numerous Chevrolet Blazer owners have reported similar coolant-related problems, including radiator failures, coolant leaks, and persistent coolant odors. These complaints are widely discussed across online forums, social media, and owner groups. General Motors appears to be aware of this recurring issue, yet many owners continue to experience failures within and outside of warranty coverage. The coolant smell is concerning because it may indicate a leak within the cooling system, which could lead to overheating, engine damage, loss of vehicle reliability, and potential safety risks while driving. Owners should not be experiencing major cooling system failures on relatively modern vehicles. I request that the federal safety agency investigate the cooling system and radiator issues affecting the 2020 Chevrolet Blazer and determine whether a defect exists that warrants a recall or other corrective action. The number of similar complaints suggests this may be a systemic issue rather than isolated incidents. General Motors should be held accountable for addressing this widespread problem and providing a permanent repair solution for affected owners. Thank you for your attention to this matter.

Filed May 17, 2026 · Engine · MI

Car is overheating with multiple engine codes. Unable to drive. Car power is reduced and shortly after will start overheating.

Filed May 11, 2026 · Electrical, Steering · FL

I am contacting you regarding my 2020 Chevy Blazer with approx $55,580 Miles. the vehicle is experiencing multiple issues consistent with the know thermostat problem reported on many 2020 Blazer, including the P0128 code, cooling fans running at high speed and "steering Assist Reduced" warnings. The Steering wheel has now become hard to turn while driving, creating a serious safety concern for me and my family, I m [XXX] old and yesterday in mother's day) while I was driving on the expressway with my grandchildren in the vehicle, the steering suddenly became very had to turn and I was almost involved in an accident, This situation was extremely alarming and poses a significant safety risk. PLEASE review many complains from owners who have experienced the same dangerous issue involving the "steering assist Reduce- Drive with Care", warning, sudden stiff steering thermostat malfunction, loss of A/C, and overheating symptoms. I urge Chevrolet and the appropriate safety authorities to investigate this issue and take immediate corrective action to avoid loss of human life. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Apr 17, 2026 · Electrical, Engine · TX

2020 Chevy Blazer RS 3.6L V6: having intermittent issues with ‘check engine’ light activating and giving code P0128 - indicating “Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)”. Symptoms include: - Temp gauge drops to reading “C” (cold), - AC blows warm/hot air, - Dash displays message, “Steering Assist is Reduced, Drive with Care”, - Radiator (electric) fans run full speed. It seems that the computer is interpreting the engine coolant temperature sensor drop as a ‘stuck open’ thermostat, thus the indicated code. However, at the same time it also appears to assume a bad coolant temp sensor, and failsafes to disable the AC and set the radiator fans to max to avoid potential overheating. The problem with this is that this can occur after driving for some period that the engine is suitably warm, then I can pull off the road, disconnect the battery for a few minutes, and everything goes back to normal operation. A broken thermostat would not behave this way. * This happened in Mar 2025 - after disconnecting the battery about 5-6 times over about a 1wk period the code cleared and we were able to pass inspection. The issue did not reoccur until about the same time this year. It has been recurring periodically since. * After reading numerous postings on this issue, with numerous different vehicles that have this engine and computer, I have no faith that the dealership will provide a solution other than charging me to replace the thermostat, and ending up with the same problem a few weeks later.

Filed Dec 22, 2025 · Engine · MI

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!

Filed Oct 30, 2025 · Engine · AL

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.

Filed May 12, 2025 · Electrical, Engine · GA

To Whom It May Concern, I am writing to formally file a complaint regarding ongoing and persistent issues with my 2020 Chevrolet Blazer. The vehicle has exhibited repeated problems that I believe may indicate a broader safety or mechanical defect, and I am requesting that the federal safety agency investigate these concerns further. Since purchasing the vehicle, I have experienced the check engine light turning on and off repeatedly, without consistent resolution. The following issues have occurred over time, all seemingly related to the engine or control systems: Engine Cooling System Failure: The first major issue involved the engine cooling system. This caused the vehicle to overheat and required service. I was concerned about the potential for engine damage or fire risk due to excessive heat. Variable Valve Timing (VVT) System Malfunction: Shortly after the cooling system issue, the vehicle began experiencing problems with the variable valve timing system. This not only affected performance and fuel efficiency but also caused the check engine light to illuminate again. Steering Control Assist Sensor Warnings: Most recently, the steering control assist sensor has started to malfunction, with warnings frequently popping up on the dashboard. This has impacted steering feel and raises serious safety concerns. Despite multiple service appointments and repairs, these problems persist or reappear. This cycle of temporary fixes without a lasting resolution is both frustrating and concerning from a safety standpoint. I am requesting that the federal safety agency look into whether these recurring engine and control system issues are part of a known defect or recall-worthy problem affecting the 2020 Chevy Blazer. Thank you for your attention to this matter.

Filed May 4, 2025 · Engine · MI

Failure of either coolant temperature sensor or thermostat or both. The A/C is disabled, the temperature gauge does not function, and a message appears on the dash display regarding steering assist not working. With all these issues, it’s impossible to feel safe driving any distances, not knowing whether the vehicle will overheat and damage the engine or other components, or if the steering will actually fail. Both parts have been replaced, at the time, May 4, 2025.

Filed Apr 17, 2025 · TX

At 41,024 the AC comoressor locked up. Took it to a repair shop. Then a year later the "steering assist light" came on. Took it to repair shop. Couldnt duplicate because it would start woring again. Had heat sensor replaced. That worked for a bit. Then it did it again. Replaced thermostate. That worked for a little bit. Then the Overheated light came on. Told me to shut the car down. (I had only drove 1/2 mile. Get out....nothing! No leaks coolant good. Had it towed to a shop And just had the thermostat changed again! Im not going to find out what happens next. I got ine more patment in tgis thing and Im trading it in. Its not a trustworthing vehicle for a single lady. Never buying a chevy again. I cannot wait to get it off my hands! 2 years everything started having issues.

Filed Feb 12, 2025 · Steering, Transmission · NC

At around 55,000 miles my Blazer began to show error codes for “Steering Assist Reduced” and “ESC”. After 60,000 it began to intermittently populate the Check Engine Light paired with the "Steering Assist Reduced" message. Then, the engine fan would turn on high, auto-start when breaking would disable, and the steering would become more stiff. Finally, I was able to get a scan on the code and found out that it was my thermostat. After taking it to my local Chevy dealer I was quoted $1100 to repair. When I called my local mechanic I was told they could fix it for cheaper, but they were unable to find an OEM thermostat in stock which usually means there's a widespread issue with that part. Upon further research, I've found a plethora of complaints online where others with Chevy vehicles are experiencing the same issue. This causes: -Greater fuel consumption -Risk for the engine to overheat -Stiffened steering which could cause accidents

Filed Dec 28, 2024 · Engine · TN

Radiator was found to be leaking. Now thermostat is sticking. This could have caused my engine to overheat and catch fire. I have had a mechanical shop replace the radiator but could not afford to replace the thermostat yet. I had been seeing warning lights and still see warnings after radiator was replaced. They said “Steering Assist Reduced” and “ESC” and the engine light came on. I went to Auto Zone Dec 9th to have them tell me what was wrong. I took to shop on Dec 13th. I have googled several complaints about Chevy blazers having this particular problems. This is apparently a widespread issue that needs to be recalled.

Filed Nov 27, 2024 · Engine · AL

The 2020 blazer is having the same coolant temperature problem the 2021 blazer has and the recall needs to be expanded. Thermostat messed up, constantly losing coolant, check engine light, steering reduced