2020 Chevrolet Blazer Engine Problems

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.

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.

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

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 have an oil leak and now they are saying both of my camshaft housing gaskets are leaking it's going to take weeks to repair cause it's such a major leak

Ongoing Engine and Steering Sensor Issues – 2020 Chevrolet Blazer I am filing a complaint regarding repeated safety and mechanical issues with my 2020 Chevrolet Blazer. The vehicle’s check engine light frequently turns on and off, and I have been informed by technicians that it is related to the thermostat system. This issue negatively affects the vehicle’s performance and reliability. Additionally, the “Steering Assist is Reduced – Drive with Care” warning continues to appear while driving, even when weather and road conditions are normal. This error is reportedly due to a steering control assist sensor, and it raises serious concerns about the safety and handling of the vehicle. The alert causes uncertainty and could potentially impact the power steering functionality, creating a hazardous driving situation. These issues have occurred multiple times despite maintenance, and they appear to be part of a broader pattern of defects affecting other owners of this model year. It is unacceptable for a vehicle this new to have persistent problems that affect both engine operation and steering safety. I urge the NHTSA to investigate these recurring issues with the 2020 Chevy Blazer’s thermostat system and steering assist sensor to determine whether a recall or manufacturer intervention is warranted. Safety should not be compromised due to what seems to be systemic defects. Thank you for your attention to this matter.

The thermostat has failed, causing hot air to blow into the car. This is a known and common issue with the 2020 Blazer.

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.

The contact owns a 2020 Chevrolet Blazer. The contact stated while driving at approximately 55 MPH and driving up an incline in the road, the check engine warning light had illuminated. The contact stated that the vehicle was shuddering. The contact stated that the failure only occurred while driving uphill. The contact had only recently taken the vehicle to a local dealer because the check engine warning light was illuminated. The vehicle was diagnosed, and the dealer determined that the thermostat and the engine control sensor needed to be replaced. The vehicle was repaired. The contact stated that approximately 1,800 miles after the first repair, the check engine warning was illuminated again. The vehicle was taken back to the same dealer. The vehicle was diagnosed, and it was determined that the air flow shutters had been damaged and needed to be replaced. The vehicle was not repaired. The manufacturer was informed of the failure and had referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 97,000.

Engine fan stuck on high, air conditioner does not work, temperature gauge stuck on cold, driving assist warning light on.

I purchased this vehicle in March, 2025 from a used dealer. When I got it, I noticed the vehicle was leaking oil on my garage floor. I took it back to used dealer who also agreed there is a leak but couldn't detect it. They sent me to Chevy Dealer. It has been 3 months now and dealer states the transmission has a seal leak. It seems like a similar recall on same year and model, however my vehicle is not listed as a recall. Why isn't there one?

I have had to replace the radiator 3 times since I've owned this vehicle. I see where there are others with the same issue. Now I have to replace the thermostat my first radiator was replaced at 16k miles. This is a safety issue because my car over heated and broke down on the highway left me stranded

Chronic code P0128, causes cooling fans to go on high, AC doesn't work and steering assist reduced. GM calls for the thermostat to be replaced, at the cost of $1400 at my local Chevrolet dealer. Worked fine for two months then code and issues come back. Online forums are full of people with the same problem. Clearly there is an issue with these vehicles with the 3.6l motor.

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.

Steering assist warning and engine check light are on. I had an scan done and was told it was the thermostat and coolant temperature sensor which seems to be a common problem. There are no safety concerns to my knowledge. I feel this problem needs to be addressed as repairs are very costly.

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

Car gets “assisted steering is turned off. Drive with caution.” Warning, temperature gauge in vehicle remains at zero/cold. Engine fan runs at full blast. Sensor gauge/thermostat is broken.