Engine And Engine Cooling Problems of Chevrolet Blazer - part 1

My 2021 chevy Blazer is leaking oil at 70,000 miles chevy only recalled under special warranty for camshaft carrier it appears chevy put in a glue for them seals that comes off unfortunately they don’t recall all Blazers just some but I am having the same issue as that special warranty. It’s a safety concern because no oil in the car can blow up the engine . 6500 to repair.

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My 2021 Chevrolet Blazer has experienced repeated problems involving the cooling system and is now exhibiting recurring symptoms that concern me about the vehicle’s reliability and safety. In 2023, the vehicle required a radiator/cooling-system repair. In 2024, it again required radiator/cooling-system repair, which was performed under warranty. The vehicle is now experiencing an abnormal humming/clicking noise from under the hood. The problem initially occurred primarily after rain but has become increasingly frequent. When the noise occurs, the air-conditioning system stops cooling properly and blows warm air. The check-engine light has also illuminated intermittently. The exact component currently malfunctioning is unknown. The vehicle remains available for inspection. Because the symptoms involve the engine compartment and follow multiple previous cooling-system repairs, I am concerned about the possibility of overheating, loss of proper cooling-system operation, an unexpected breakdown while driving, or another mechanical failure that could place the occupants or other motorists at risk. Authorized Chevrolet dealerships previously inspected and repaired the vehicle’s cooling system in 2023 and again in 2024. Despite those repairs, significant symptoms have returned. The current problem has not yet been definitively diagnosed, so I cannot state that the present failure is the same component previously repaired. The warning symptoms include the abnormal under-hood humming/clicking, loss of cold air from the air-conditioning system when the condition occurs, and an intermittent check-engine light. The symptoms have become more frequent over time. I am reporting this because of the recurring nature of the problem and the vehicle’s history of multiple cooling-system repairs. I request that NHTSA document and evaluate this complaint together with any similar complaints involving this model and model year.

Vehicle information: 2021 Chevrolet Blazer 2. 5l engine, VIN [xxx]. Odometer 118000 miles. Description of incident: while operating the vehicle, the mechanical brake vacuum pump experienced a catastrophic internal failure. The drive gear housing shattered violently without warning, shearing off the end of the connecting engine camshaft. Because this was an instantaneous mechanical failure, the vehicles computer did not trigger any dashboard warning lights, check engine lights, or safe mode protocols prior to the failure. Safety hazards and component damage: first, the total destruction of the vacuum pump caused an immediate compromise to the brake booster vacuum lines, resulting in a sudden, dangerous loss of power braking assistance. Second, the sheared camshaft breached the engine valve cover or head, causing the engines pressurized oil system to instantly dump all engine oil externally onto the ground. Third, shrapnel or violent structural torque from the instant engine seizure punctured or severed the adjacent transmission cooler fluid lines and compromised brake fluid lines, causing total loss of transmission fluid and brake fluid simultaneously. Request for action: this failure mirrors the exact mechanical defects documented in gm technical service bulletin 21-na-268 and previous gm vacuum pump recalls like NHTSA recall 19v-645, which excluded the 2021 Blazer. I am filing this report because the lack of an electronic warning indicator before a catastrophic mechanical brake and engine failure poses an extreme, immediate threat to highway safety. Gm must expand recall coverage or issue a special coverage adjustment for this model year. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

Car will not crank, stalled while cranked, throws code p023f.

Thermostat went bad at 47,500 miles. Temp gauge stopped working, engine light came on and alert stating steering assist is reduced.

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My 2021 Chevrolet Blazer rs equipped with the 3. 6l lgx v6 experienced catastrophic engine failure at approximately 90,200 miles. The vehicle had no prior warning. The dealer diagnosed the timing chain / lift/ cam damage. I am requesting investigation into whether this represents a safety or durability defect affecting other vehicles.

The car just stopped while I was driving. I was in an intersection. The car would not turn back on.

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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 vehicle’s radiator developed a coolant leak that was discovered and confirmed by the dealership during a routine oil change, tire rotation and state inspection. There were no warning lights, warning messages prior to the dealership discovering the leak. The radiator required replacement. The dealership also told me that they had the replacement radiator on hand because this type of radiator failure had been occurring fairly often with this type of vehicle. The radiator failure presented a potential safety concern because a coolant leak can worsen without warning and result in a sudden loss of coolant, engine overheating, or vehicle breakdown while driving. Because there were no warning lamps or other symptoms before the leak was discovered, we may not have had any indication that the cooling system was failing. The problem was confirmed by the dealership during inspection, and the dealership determined that the radiator was leaking and needed to be replaced. The vehicle/component was inspected by the dealership. No manufacturer, police, or insurance inspection has occurred, to my knowledge. There were no warning lamps, messages, overheating, or other noticeable symptoms prior to the dealership finding the leak. The vehicle is only three years old, with 39000 miles on it at the time of the failure. I am reporting this because a radiator failure at such a young vehicle age, particularly one that develops without any warning to the driver, could potentially create a safety hazard if the coolant loss becomes severe while the vehicle is being operated. I’ve seen many complaints in online forums that this is an ongoing issue with these radiators used by chevy. It seems the replacement radiators are having the same issues. Why can’t something be done? dealership information: #1 cochran Chevrolet cranberry 22010 perry highway zelienople, PA 16063.

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The radiator and thermostat on my 2020 Blazer had to be replaced at less than 35,000 miles. It was out of warranty and the chevy dealer charged me $3,500 to replace them. Internet sources state that this is a common problem with this car. I complained to chevy corporate and they refunded $1,000. I do not feel this was a fair settlement due to the fact that it is a common problem.

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I was driving and steering reduced drive with caution notification and brake assist notification came on and then engine light and the temp gage went to cold and stayed there. My steering stiffened up making it hard to steer. This is a known problem with the chevy Blazers and it had to do with the thermostat needing replaced.

The contact owns a 2022 Chevrolet Blazer. The contact stated that the coolant was leaking from the radiator. There were no warning lights illuminated. The vehicle was taken to the local dealer, where it was diagnosed and determined that the radiator needed to be replaced. The contact was informed that the dealer was replacing a lot of radiators for similar failures. The vehicle was not repaired. The manufacturer was contacted, and a case was opened. The failure mileage was approximately 49,500.

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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.

The contact owns a 2023 Chevrolet Blazer. The contact stated that while driving 10 mph and pulling into a parking lot, the sun gear and the drive shaft fractured. The vehicle became inoperable. The vehicle was pushed to a safe place. The check engine warning light illuminated after the failure. The contact associated the failure with NHTSA campaign number: 23v172000 (power train). The vehicle was towed on a flatbed to the local dealer. The vehicle was not diagnosed or repaired. The dealer provided an estimate for the transmission replacement. The manufacturer was contacted and confirmed that there was no recall coverage on the VIN for the failure. The manufacturer referred the contact to the NHTSA hotline for assistance. The failure mileage was approximately 107,000.

"while attempting to merge onto a high-speed freeway on-ramp, the vehicle suffered a sudden and catastrophic loss of engine power, rendering it unable to accelerate and creating an immediate life-threatening safety hazard. The vehicle was restarte and driven home, where an onboard diagnostic check revealed an emissions system failure. The dealership later confirmed that both close-coupled catalytic converters on the 3. 6l v6 were damaged. The check engine light was a solid light. Not flashing.

Just had to replace a radiator that was leaking all across the top. Also have gotten the steering assist warning for thermostat and temperature sensor. Seems to be cery common problems rhat gm ahould fix.

Engine temp gauge bottoms out because the thermostat is stuck open, causing the air to stop working. Also a warning that the steering assist is reduced. Eng check light comes on with a code p0208. This a known problem with an extended service # (n242484760) but only if your VIN is listed. All vehicles with this problem should be covered.

Engine temp gauge stops working causing the air to stop working and the cooling fan to rev to highest rpm. Also a warning that the steering assist is reduced. Eng check light comes on with a code p0208. This a known problem with an extended service # (n242484760) but only if your VIN is listed. All vehicles with this problem should be covered.

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.

P0128code p0024 code second cam shaft sensor failure thermostat failure, stuck open electrical issues from low battery power failure to shift to park when shutting off vehicle.

P0128 code produced when scanned. Cooling fans on high. No ac. Steering assist warning. Had to replace the thermostat. Ecm also replaced and caused the tire pressure sensors to fail and had to replace the tire sensors. There is a recall on models 2021 to 2025 but none on the 2020 for the thermostat. I have paid $3500. 00 to have my vehicle fixed.

The check engine light came on with a warning that said "steering assist reduced drive with care". The temperature gauge went to cold and the air condition quit working.

Thermostat stuck open radiator broke. Told by 4 gm dealerships, this is a very common problem in a gm 3. 6l v6. Gm even claims it's common in its tech advisements. The "stuck open" glitch (p0128 code).

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

Vehicle safety defect complaint – 2023 Chevrolet Blazer to whom it may concern, I am submitting a formal safety defect complaint regarding my 2023 Chevrolet Blazer. This vehicle has exhibited multiple system failures that present a serious risk to driver safety and public roadway safety. The vehicle was purchased new on July 20, 2023. Beginning on April 21, 2025, at approximately 27,610 miles, the vehicle developed a progressive defect initially presenting as oil-related issues. Despite multiple repair attempts, the condition worsened and required a full engine replacement in January 2026. Following the engine replacement, the vehicle continued to experience critical safety failures, including engine stalling, reduced engine power warnings, and electronic stability control (esc) alerts. On April 26, 2026, the vehicle experienced a driver assistance system malfunction in which it attempted to steer off the roadway. I was forced to manually disable the system to maintain control of the vehicle. On April 27, 2026, the vehicle exhibited a fuel system failure, including fuel leakage and fuel odor, along with multiple simultaneous warning indicators: • reduced engine power • service esc • steering assist reduced / drive with care • power assist driver system disabled this combination of failures presents both a fire hazard and a loss-of-control risk. Additionally, I was informed by the dealership that a high-pressure fuel line, a one-time-use component, was not replaced during the engine installation. This raises concerns regarding improper repair and continued unsafe operation of the vehicle. The vehicle has undergone multiple repair attempts and a major powertrain replacement, yet continues to present serious safety concerns. Due to these ongoing issues, I do not feel safe operating this vehicle. I respectfully request that NHTSA review this matter for potential safety defects that may impact other vehicles of the same make and model.

The contact owns a 2024 Chevrolet Blazer. The contact stated that while driving 20 mph with 100 miles of charge, the vehicle stalled and shut off. The screen was black, unresponsive, and failed to start. The vehicle was towed to the local dealer, where it was diagnosed with a power module failure. The part was on back order. The electric module was previously replaced. The vehicle was not repaired. The manufacturer was contacted, but no assistance was provided. The failure mileage was 10,381.

I have a 2022 Blazer with a 3. 6 engine. The thermostat has failed and dealer says only certain Blazer vehicles are covered under aspecial warrnty exstesion. I know several people having the same problem. I have a check engine light, with a scan shows code p0128(thermostat0. I also have a display of power steering assist reduced and tempature gauge stays much lower than normal. . When you turn vehicle off the high speed cooling fans remain running ub=ntil battery is dead.

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?.

A/c quit working, "caution power steering assist . . . . Working, temperature gauge reading zero ( far left side of gauge. Pf62f code set. Repair shop says very common. $800 to repair due to removal of plenum and other component including water temp sensor and thermostat while your there. $100+. 63k miles on vehicle.

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.

I have received this warning a few different times “steering assist is reduced". Which causes my vehicle to not blow cold air when ac is on. Fans are louder than normal. And when I turn off my vehicle fans continue to run for roughly around 8 minutes.

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.

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.

The vehicle will not shut off when you shift to park. You are forced to sit in the vehicle for extended periods of time attempting to get the vehicle turned off. Apparently chevy is familiar with eat problem and there are pending class action law suits in ohio. According to the dealership chevy has acknowledged there is a defect but no recall has been issued. We have had this issue for about two months and it is getting worse.

My drive assist stopped working. Then my air conditioning stopped blowing cold. Then the temperature gauge stopped working. Upon turning the car off the fan continued to run for several minutes. Took to repair shop where it required a new thermostat housing, coolant temp sensor and coolant flush. The total cost for repair was $1,131. 52. The car has 37,000 miles on it. Barely out of warranty. This is a well-known issue among chevy owners.