2021 Chevrolet Trailblazer Engine Problems

My timing belt snapped prematurely, causing a total loss of engine power while driving on the highway, which is a severe safety hazard

NHTSA ID

11754543

Incident

Jul 29, 2026

My trailblazer will not shift properly into drive from park or reverse. GM calls this a "loss of forward motion" or "delayed forward engagement" in their service bulletin TSB-24-NA-009. It is a safety issue because you never know when or how long the vehicle will take to engage and allow forward movement. This causes issues when leaving a parking spot or a driveway, especially on busy roads. If the car will not move forward, my family is stuck in the road until it finally engages into gear and allows forward movement. When this occurs, the vehicle engine will shutter and not allow any forward movement. I usually have to move the drive selector back to park and back to drive again. This creates an immediate and unreasonable safety risk because the vehicle will not move for several seconds while I am sitting in traffic. This generates a P2714 code. I had the car looked at by a GM dealer as well as an independent transmission repair shop and both indicate it will likely need a new transmission. GM is fully aware of the defect and has issued a service bulletin, TSB-24-NA-009 to instruct dealers how to diagnose and repair the problem. The bulletin proves a widespread engineering or manufacturing flaw exists. However, GM is treating this as a maintenance issue rather than the severe safety hazard that it is. It is my understanding, GM has since abandoned this transmission on the newer models, further indicating that GM knew these transmissions were not designed well. I am requesting the NHTSA office cross-reference my complaint with GM TSB-24-NA-009 and upgrade the component defect to a mandatory, manufacturer-funded safety recall before it causes a collision or fatal injury. Thank You

NHTSA ID

11752367

Incident

Jun 30, 2026

Reduced engine powers caused by turbo charger underboost, at 91200 miles.

NHTSA ID

11751316

Incident

Jul 18, 2026

car was driving fine, went up a hill then check engine light came on with warning that stated "reduced engine power." drove it approx 8 min to home. parked in garage. Next morning, took to Firestone Complete Autocare as that was the first place available. Just got a call that the whole turbo assembly needs to be replace costing almost $2000 and will be without a car for about a week. 5 year warranty expired 3 months ago and there is less than 47,000 miles on it. It is currently at the shop so I don't have a bill yet, but they told us how much when they told us what was wrong with it. This is unacceptable! Reading about and hearing about this complaint all over the internet!!!

NHTSA ID

11749711

Incident

Jul 10, 2026

2021 Chevrolet Trailblazer RS (123,000) - Coolant control Valve failure Cooling issues after 20-25 mins of driving. No Check engine lights initially just temperature gauge climbing. After 3 day of trying to drive to and from work. "Engine reduced" and P3075 code. Had it towed to dealership, in which they replaced the water pump. This DID NOT fix the issue. The next two drives (from work, and to work), I had to pull off the road several times to get the car cooled down, and run heater on full blast to drop temperature. Pulling off the road in heavy interstate traffic consistently because of the Coolant Control Valve (25207464 GM). Not to mention me, looking at the temp gauge most of the way to work, versus eyes on the road. The old thermostats would at least give you a temperature code, and not an Engine Coolant Flow Too Low error which leads to water pump being replaced erroneously. Going to plastic control valve next to a hot engine, sounds as good as plastic car jacks for this car. Oh, wait, that happened to me as well, and they recalled it after it broke on me at 2 am in the morning.

NHTSA ID

11731922

Incident

Mar 19, 2026

While driving down the interstate my 2021 Chevy Trailblazer suddenly flashed "Battery Saver Mode" on the dash and shut off completely. I was able to coast to the side of the road and call for help. This was a MAJOR safety issue as my 4 year old son was riding with me and we could've caused or gotten into a serious accident. There were no previous warnings and no Check Engine Light came on prior to it shutting off--I had been having no issues. The car will not turn on and when attempting to, it makes a screeching noise. I had to get it towed to a local service center who stated my car has "catastrophic engine failure". They advised the issue could be either "timing chain or a dropped valve"--unable to confirm until they take the engine apart completely. They denied issues with the battery or starter and said the engine was completely blown. There was less than 120k miles on it and i kept up with maintenance.

NHTSA ID

11731702

Incident

Apr 5, 2026

Coolant control valve replacement after 5 years of purchasing the vehicle. Put at risk of over heating while driving, fan stays on after vehicle is turned off. Problem confirmed by 2 dealerships. Check engine light on for a long time, fan over working, staying on after the vehicle is off. The only warnings were the engine light coming on to get inspected and fan over running. 1st came up in December 2025 and it is now almost April 2026 costing me $1600 in repairs!! There are other Chevy models that this looks like it is being covered for but my vehicle is having this issue now and is not being covered?!?? Ever since i bought this vehicle brand new in 2021 it was labeled a lemon and have had nothing but issue after issue after issue!!

NHTSA ID

11727889

Incident

Dec 19, 2025

VEHICLE WAS TAKEN TO DEALERSHIP FEB 2026 FOR TURBO/WASTEGATE REPAIR (P0299). MARCH 22, 2026, VEHICLE STALLED AND SCREEN SAID TO SHIFT TO NEUTRAL AND PUSH TO START AGAIN. CAR WOULD CRANK BUT NOT START (SOUNDS LIKE THERE IS NO COMPRESSION). HAD VEHICHLE TOWED TWO MILES TO RESIDENCE AND CONNECTED TO OBDII SCANNER, WHICH SHOWED 6 NEW CODES (P0006, P228C, P0089, P0340, P0365, P0299).

NHTSA ID

11727149

Incident

Feb 12, 2026

When stopped at a red light & the light turns green & I accelerate, the vehicle does not move. It makes a loud noise and jumps. This happens way too many times. There’s also an issue with the brakes, when you press on them, you can hear something grinding, which should not be happening because I bought the car brand new. Also the brakes have always been super squeaky, which is very frustrating because they should not be with a brand new car once again. The engine light goes on and off randomly and doesn’t say anything.

NHTSA ID

11726811

Incident

Feb 1, 2026

I was driving an hour away from home and suddenly my muffler and exhaust started dragging— 49,000 miles, 5 years old AND just passed inspection A WEEK AGO. Luckily, it didn’t become completely unattached because that could have caused an accident as there were cars behind me. Complete safety hazard

NHTSA ID

11722752

Incident

Mar 7, 2026

This vehicle was sold as new when this vehicle had a defective Turbo Underboost issue from a ECM Issue previously prior to the 2022 Trailblazer being sold to us. This vehicle has a shift to park issue which sticks when you try to Park the vehicle. Next This vehicle has had 4 prior incidents of attempted repair of this Turbo Underboost and a failure to pass emissions which lead to the engine and transmission failure of this vehicle. I have waited since July 6, 2025 of this vehicle being in the shop no rental no loaner. Now no replacement vehicle. For more than nine months and a General Motors open claim since 07/06/2025! GM is hiding the truth about Recalls and Road Hazards not listed to vehicle like this 2021 Trailblazer and other GM vehicles that GM refuses to replace and cannot repair or cover the additional financial hardship placed on unwitting consumer as they sell defective vehicle wholesale or as new vehicles through Chevrolet Dealership across this goble. We must STOP this from happening. GM is not even honoring the Government Guidelines forcing victims to hire counsel to buy time and prevent massive Recalls like ours.

NHTSA ID

11720307

Incident

Jul 5, 2025

The issue is the yellow engine light lit up on the dash of my 2021 Trailblazer in late August of 2025. At the same time, the cluster displayed the message "Engine Power is Reduced". Over the next few weeks my car engine would randomly stall out while I was driving! As you can imagine, this is a very unsafe driving condition. My car stalls and I'm in traffic and have no ability at all to control the vehicle. This happened at least 4 times to me. When I checked the On Board Diagnostic codes on my vehicle the system reported back U060F (Mass Air Flow Sensor). I searched online for this condition with 2021 Trailblazers and found GM Service Bulletin number 22-NA-008, dated March of 2022. This Service Bulletin clearly shows that Chevrolet were well aware of a problem years before it occurred to my vehicle. So, in October I took my car to Bowman Auto Center, explained all of the above to them, and I mentioned the Service Bulletin that I found. Their investigation found that, indeed, the cause of my engine stalling was broken wires to the Mass Air Flow sensor (MAF sensor). Bowman repaired my car and billed me $364.44 as shown on the attached 2-page Repair Order. I tried to make the case with the Bowman Service Department that this should be a warranty repair, and paid by GM. Bowman responded that it was only a Service Bulletin from GM for the issue, and the customer is responsible for payment. I am astonished that repair of this product Design Failure, which results in an unsafe driving condition, would be paid for by the customer! The reason I call it a Design Failure is because NO wiring should break during the life of a vehicle. Engines rock and move, and the Trailblazer design should have compensated for this engine movement by having a sufficient slack loop designed into the wire harness leading to the Mass Air Flow sensor. I filed a case with Chevrolet, number 80982656, but they declined my request for reimbursement $$.

NHTSA ID

11700638

Incident

Aug 27, 2025

The contact owns a 2021 Chevrolet Trailblazer. The contact stated that after reversing, the transmission was shifted to drive (D), but the vehicle failed to immediately recognize the selected gear. The check engine warning later illuminated. The vehicle was taken to an independent mechanic, who determined that the under boost, transmission control module, and transmission control solenoid had failed, and there was a loss of communication with the radio and loss of communication with the telematic control module. The mechanic advised the contact to take the vehicle to the dealer for assistance. The vehicle was not repaired. The manufacturer was made aware of the failure and advised the contact to report the failure to the NHTSA Hotline. The failure mileage was approximately 42,000.

NHTSA ID

11693768

Incident

Aug 31, 2025

Mileage

42,000 mi

Experiencing reduced speed, rattling noise, check engine light, power steering light on. Chevy app shows throttle control system and antilock break system error messages. Took to Chev dealership. Advised it was fuel injector (1 /4 was burned out). Had all 4 replaced ($3000). Picked up car on a Friday, vehicle was having the same issues next day Saturday. Took it back on Monday, it is now Wednesday and they’re saying it’s the turbo charger now (another $3000). Mechanic couldn’t figure out what the issue was so it took 3 days for him to now say it’s the turbo charger. I think it was the turbo charger from the get go! What’s the purpose of the diagnostics ($250)? Isn’t it to pinpointed the issue? 1st day, took him 4 hours to say it was the fuel injector. 2nd time around it took 3 days. I kept showing them and telling them it’s the throttle control system! They’re trying to rip me off! Mechanic is saying he’s been test driving it and no issues. I took a photo of my mileage before I handed them my car and it was 79,190. The mileage today says 79,191. How and where is he test driving it if it’s only been 1 mile? Reverse and forward ? They’re lying

NHTSA ID

11690808

Incident

Sep 15, 2025

vThe 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. No warning lights were illuminated. The vehicle was taken to the dealer, where it was diagnosed with a crack between the muffler and front pipe. The contact was informed that the muffler needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure but provided no assistance. The contact was advised to contact the NHTSA Hotline to report the failure. The failure mileage was approximately 57,850.

NHTSA ID

11678883

Incident

Aug 1, 2025

Mileage

57,850 mi

Month of June of 2024 I purchased 2021 Chevrolet Trailblazer LT with 31k miles on the odometer I had to service my vehicle and had to replace the fuel pump, took weeks to get in due to the strike that took place, Chevrolet will not back behind their employees nor their consumers. They only honored me 15pts on my vehicle, a few months pass and more issues arise one being the manifold sensor (a) and then another two days on the road the wiring harness thankfully my car was under a secondary warranty and I paid $200 per repair, although this became a very costly month being $600 car payment and $400 in repairs in a matter of a few months owning the vehicle, I am having similar issues again with the wiring harness a year later.

NHTSA ID

11666643

Incident

Apr 19, 2024

The contact owns a 2021 Chevrolet Trailblazer. The contact stated while driving at an undisclosed speed, the vehicle inadvertently lost motive power and was unable to accelerate above 40 MPH. The contact stated that after the failure, the vehicle went into LIMP Mode. The check engine warning light was illuminated. The vehicle was taken to the dealer, who diagnosed a failure with the variable valve timing system. Additionally, the dealer found that the intake camshaft actuator was incorrectly positioned, resulting in damages to the exhaust camshaft. The vehicle was not repaired. After investigating the failure, the contact related the failure to NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling), but the VIN was not included. The manufacturer was notified of the failure but provided no assistance. The failure mileage was 81,000.

NHTSA ID

11666344

Incident

Jun 8, 2025

Mileage

81,000 mi

The contact owns a 2021 Chevrolet Trailblazer. The contact stated that while the vehicle was parked, the vehicle was turned off however, the blower fan independently activated. No warning light was illuminated. The contact's husband had just parked the vehicle upon arriving at the place of employment. The contact's husband is a certified mechanic. The vehicle was diagnosed with coolant intrusion and a misfire in the engine. The contact was informed that the spark plugs needed to be replaced; however, the spark plugs had to be ordered. The vehicle was not repaired. The vehicle was driven to the residence. The contact's husband parked the vehicle and turned the vehicle off. The vehicle failed to start as intended and was towed to the dealer to be diagnosed and the dealer determined that there was a crack in the head gasket. The contact was informed that the head gasket needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The contact was advised to contact the NHTSA Hotline to report the failure and a case was filed. The failure mileage was approximately 128,000.

NHTSA ID

11657316

Incident

Apr 7, 2025

Mileage

128,000 mi

My vehicle keeps flashing: "Shift to park" when I am in park and then my car is unable to shut off the battery even though I'm in park and our of the vehicle

NHTSA ID

11652696

Incident

Mar 26, 2025

On [XXX] while driving on the highway my check engine light came on. The car turned off while going 60MPH on the 18 mile stretch towards Miami from Key west and luckily there were no cars around me. I checked for the code and it was P1467 for the Evap Purge Pump. I took it to a dealership in Miami and they told me it would be fine to drive that the part needed to be replaced. I drove back to key west and bought the replacement part. That same part did not work. I checked to see if the part was receiving voltage and it was. So i will continue with going to the dealership. My wife and son have developed a cough from having to constantly smell the fumes due to their existing asthma. I will never buy another chevy again.

NHTSA ID

11649945

Incident

Mar 19, 2025

On numerous occasions (typically when needing to accelerate into the flow of traffic), the Reduced Engine Power message and engine light came on, the car rapidly decelerated to 35 mph, and would not accelerate rapidly. Turbocharger, waste gate actuator, and other parts need replaced and reprogrammed, but issue persists. On one occasion, power was reduced and car was stuck "revving" at 25 mph. I have had to swerve off the road to avoid a crash of being rear-ended. Issue started around 60,000 but has happened at least 5 separate times.

NHTSA ID

11640587

Incident

Jan 30, 2025

IN January my fuel gage stopped working , unable to know how much gas I had. The fuel pump and floater needed to be replaced If fuel was not getting to the engine the vehicle would stop working causing a possible accident with other drivers . I did not use this vehicle for many days until a mechanic cleared for useage . It cost me $320.00 of my own money to fix this for safety concerns. As of today 1/22/25 I has been fixed by A-Plus in North Fort Myers.

NHTSA ID

11637782

Incident

Jan 3, 2025

Reduced engine power, code P0014. Camshaft actuator oil control valve bolt stuck open. All the signs and symptoms per bulletin released by NHSTA to repair if not sold yet. Extremely hazardous when accelerating to get on highway and engine power reduces.

NHTSA ID

11623400

Incident

Jan 2, 2024

On [XXX] I shifted my 2021 Chevy Trailblazer to park and and was unable to shut off the vehicle. When I shifted it to park it kept displaying an error "Shift to Park" on the dashboard, but the shifter knob was correctly in park. I attempted to press the power button to turn off the car and it wouldnt do anything but beep. I tried multiple times to shift to park to get the car to recognize it was actually in park and turn off the vehicle but I was unable to do so. I was frantic and panicked to find I could not turn off my vehicle as I park on a apartment complex lot. That day I took the car to Henna Chevrolet in Austin Tx for repair. They said the part was on backorder from GM with no ETA. It is now November 1st and there is still no ETA on when I will get the part for my car from GM. This has been going on for 3 weeks now with no end. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11623129

Incident

Oct 11, 2024

My 2021 Chevy Trailblazer has an error reading “shift to Park” that randomly appeared 2 weeks ago, now is doing it almost every time I stop my car, error has also cause my battery to die. When error is showing my car will not shut off. Took to a Chevy dealer and recommended changing the gear shift assembly, can’t guarantee it will fix the problem. They have ordered the part but $450 plus parts and labor for not a guarantee is concerning. I also travel for work and have been left stranded because of this issue.

NHTSA ID

11612155

Incident

Aug 19, 2024