2021 GMC Acadia engine problems

ENGINE

Display suddenly says "Steering assistance reduced, drive with care" Temp gauge goes to C and stays there. Radiator fans speed up and stay on after the car has been turned off. Dealer unable to find a diagnostic code for the problem.

NHTSA complaint #11741035 — an unverified report by a vehicle owner.

ENGINE

I am submitting this complaint regarding ongoing mechanical and electrical issues with my 2021 GMC ACADIA that have been occurring intermittently for approximately the past year and a half. The primary issues involve the coolant temperature sensor, thermostat system, engine cooling fan, and dashboard warning messages. The vehicle repeatedly experiences problems related to the coolant temperature sensor and thermostat. During these episodes, the engine cooling fan continues running even after the vehicle has been turned off, sometimes for an extended period of time. In addition, the dashboard frequently displays the warning message: “Steering Assist is Reduced – Drive With Care.” These warning messages and symptoms occur off and on without consistent resolution. The vehicle has already undergone repairs, including replacement of the radiator, yet the problems continue to return. Despite previous service attempts, the underlying issue has not been permanently corrected. The recurring nature of these problems raises concerns about the reliability, safety, and dependability of the vehicle, especially considering the steering assist warning and possible overheating or electrical system concerns connected to the cooling system malfunction. The repeated failures have caused significant inconvenience, concern for safe operation of the vehicle, loss of confidence in the vehicle’s reliability, and ongoing disruption due to repeated repair needs. I am requesting a thorough diagnosis and permanent repair of the coolant temperature sensor, thermostat, cooling fan system, and any related electrical or control module issues contributing to these recurring problems.

NHTSA complaint #11736741 — an unverified report by a vehicle owner.

ENGINE

Bought the acadia in june of 2021, in december of 2022 had to have the radiator replaced due to it leaking. This was found on routine maintenance and was not having any issues whatsoever. I received no alerts on my dash such as a check engine light. Fast Forward to March 2026, I received a message of "steering assist reduced. drive with care." The engine seemed like it was still running despite the car being off. This was happening intermittently and definitely not every time I drove. I made an appointment for the regular oil change and to have this message investigated. Initially they told me it was the temperature regulator, however, they put a new regulator on and tried to re-pressurize the system. The system failed to re-pressurize due to the radiator leaking AGAIN. Of course, there was a 2 year warranty on the radiator after it was replaced initially and now we are about a 1.5 years outside the warranty.

NHTSA complaint #11736208 — an unverified report by a vehicle owner.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Acadia. The contact stated that while driving at an undisclosed speed, the check engine warning light illuminated. In addition, the coolant fan was running after the engine was turned off. The vehicle was taken to Auto Zone to be diagnosed due to the check engine warning light being illuminated. The contact was informed that DTC: P1098; was retrieved, which indicated a fault with the coolant control valve. The vehicle was taken to the dealer, where it was confirmed that the coolant control valve had failed. The vehicle remained at the dealer unrepaired. The contact related the failure to the Manufacturer Recall Number: N252508341. However, the VIN was not included in the recall. The manufacturer was made aware of the failure and advised that the VIN was not under recall. The failure mileage was approximately 69,000.

NHTSA complaint #11725820 — an unverified report by a vehicle owner.

ENGINE

Car has had multiple issues with check engine light coming on for the last 2 years and stays on especially during the winter months. The purge pump has failed multiple times. The cooling fan has run after engine shutting off for multiple years now. The thermostat has been failing for the last 6 months. Now yesterday low power protection suddenly turned on driving on the expressway limiting power in the middle of traffic. Was able to get off at exit without accident and get car home. I guess we have to pay out of pocket to get fixed. This is a known issue that GM fails to include every VIN with the 2021 year or certain models and VINS.

NHTSA complaint #11721893 — an unverified report by a vehicle owner.

ENGINE

Car was taken in for an oil change at 62k Miles. Dealer advised that it needed a radiator replaced. At 64k miles it was brought into the dealer for warranty work due to a failing thermostat. While being diagnosed, we were told not only the radiator needed to be replaced, but the oil cooler also needed to be replaced. So a 5 year old car with just over 60k Miles had the thermostat/sensor fail and need to be replaced. A radiator fail and need to be replaced and and an oil cooler fail and need to be replaced. Vehicle has been at a GM dealer for all maintenance. No crashes or reasons these parts should fail. Vehicle has never towed anything to but any sort of strain on the cooling system.

NHTSA complaint #11718832 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2021 GMC Acadia. The contact stated while driving at an undisclosed speed, the check engine warning light illuminated and DTC: P04FB; was displayed. The vehicle was taken to the dealer where it was diagnosed with moisture of the crank case. The vehicle was repaired. The contact stated that the failure was a quick fix and was covered under the warranty. The contact stated that the failure had occurred several times and was covered under warranty. The contact was informed that there was no fix for the failure. The manufacturer was not made aware of the failure. The failure mileage was approximately 37,000.

NHTSA complaint #11716760 — an unverified report by a vehicle owner.

ENGINE AND ENGINE COOLING:ENGINE:CRANK/CAMSHAFT POSITION SENSOR

The contact owns a 2021 GMC Acadia. The contact stated while driving at an undisclosed speed, the check engine warning light illuminated and DTC: P04FB; was displayed. The vehicle was taken to the dealer where it was diagnosed with moisture of the crank case. The vehicle was repaired. The contact stated that the failure was a quick fix and was covered under the warranty. The contact stated that the failure had occurred several times and was covered under warranty. The contact was informed that there was no fix for the failure. The manufacturer was not made aware of the failure. The failure mileage was approximately 37,000.

NHTSA complaint #11716760 — an unverified report by a vehicle owner.

ENGINE

Been happening for a year and a half. Muffler is very loud and rattles constantly. Getting worse over time. There is a current recall but my vin isn’t included even though my car is having the same issue.

NHTSA complaint #11712579 — an unverified report by a vehicle owner.

ENGINE

VEHICLE'S ENGINE INCURRED COOLANT TEMPERATURE ISSUES, SET DTC CODE, AND COOLING FAN RAN AFTER ENGINE WAS TURNED OFF. DEALER DIAGNOSED AS THERMOSTAT FAILURE AND COMPLETED REPAIRS. DEALER CHECKED AND FOUND NO SERVICE ASSISTANCE FOR REPAIR EVEN THOUGH THERE WAS A BACK ORDER FOR REPLACEMENT PARTS AND WAS SECURED THROUGH DEALER IN DETROIT CURRENT NHTSA ID NUMBER 110243390 / MFG COMMUNICATION # N252508350 REFERRING TO 3.6 V-6 ENGINE. GMC DECLINED ANY MONETARY ASSISTANCE TOWARDS REPAIRS WITH 76278 MILES I ALSO OWN A 2020 CHEVROLET BLAZER WITH A 3.6 V-6 ENGINE THAT EXPERIENCED SAME FAILURE PAID $400 DEDUCTABLE TOWARD REPAIR

NHTSA complaint #11701422 — an unverified report by a vehicle owner.

ENGINE

For the 3rd time of ownership the cooling fan stays on after vehicle is turned off and the display “steering assist is reduced, drive with caution”.

NHTSA complaint #11701173 — an unverified report by a vehicle owner.

ENGINE

The thermostat failed which cause the steering system to fail and car to not read temperature

NHTSA complaint #11701121 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2021 GMC Acadia. The contact stated that while his wife was driving at an undisclosed speed, the vehicle inadvertently lost motive power. The driver was able to coast to the shoulder of the roadway, where the vehicle failed to restart. The check engine warning light was illuminated. The vehicle was towed to an independent mechanic, who diagnosed a failure with the fuel pump control module. The vehicle was repaired. The manufacturer was notified of the failure but provided no assistance. The failure mileage was 36,970.

NHTSA complaint #11700332 — an unverified report by a vehicle owner.

ENGINE

GM need to be looked at for faulty Thermostats being put into vehicles. While driving the message "steering assist is reduced " You get to a safe place and shut you car off and the fan still runs. After speaking with my dealer today, he said he has done 7 in last week. And if you look online, everyone especially Acadia models is having this problem. Customers are getting charged alot of money for the repair. To me this is a defective thermostat on GM and needs to be addressed

NHTSA complaint #11699969 — an unverified report by a vehicle owner.

ENGINE

I was driving home and about 10 minutes into my drive I got a notification about my steering assistance being disabled. When I arrived home about 10 minutes or so later and went to shut my car off I noticed that a very loud fan sound from the hood of my vehicle began roaring. I restarted my car and it went away. I looked at my temperature gauge and it was all the way on C. I tried shutting my car off again and the loud electrical fan sound picked right back up again. I stayed in my vehicle while it was turned off waiting to see if it would stop while trying to call for answers. I couldn’t risk having a dead battery for work tomorrow morning. After what was about 6-7 minutes the electrical fan finally shut off. Turns out my aunt JUST had this exact same issue with her 2021 GMC Acadia as well. According to Reddit MANY people are having this issue yet there is still no recall for this problem. My car is only at 85K miles, has always been dealership maintained and has never had any issues like this until now. If this is a wide spread make and model issue a recall should have been issued.

NHTSA complaint #11697020 — an unverified report by a vehicle owner.

ENGINE

I have a 2021 GMC Acadia that keeps saying steering assist not available. But when it does this, the temperature gage stops working and so does the AC. After you turn the car off the fan still runs for at least 10 minutes.

NHTSA complaint #11688739 — an unverified report by a vehicle owner.

ENGINE

This is a well known issue. On the dash it keeps reading steering system is being reduced drive with care. I have been dealing with this issue almost years. Been to the dealership too many times for this issue

NHTSA complaint #11685299 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2021 GMC Acadia. The contact stated that after a routine maintenance at the local dealer, it was noticed that the radiator was leaking coolant. Upon further inspection, the contact and his son noticed that the driver’s side of the radiator was corroded. No warning light was illuminated. The vehicle was not repaired due to the cost. The manufacturer was made aware of the failure. The failure mileage was approximately 32,175.

NHTSA complaint #11663643 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2021 GMC Acadia. The contact stated while driving at an undisclosed speed, the check engine warning light illuminated. The vehicle was taken to the dealer where it was diagnosed with a fractured rear cap catalyst converter cap. The contact was informed that the catalyst converter needed to be replaced. The vehicle was not repaired. The contact stated that the original catalyst converter was replaced by the same dealer less than two years ago under warranty. In addition, the contact stated the front catalyst converter was replaced by the same dealer five weeks ago. The manufacturer was made aware of the failure but provided no assistance. The contact was advised to contact the NHTSA Hotline and report the failure. The failure mileage was approximately 86,000.

NHTSA complaint #11656325 — an unverified report by a vehicle owner.

ENGINE

While driving the engine cut out. I wasn't able to get the vehicle off the road and had to put in an acceleration lane until I could get a tow. Other drivers entering the roadway were accelerating and some didn't realize that my road hazard lights were on and almost hit me. The vehicle was given a diagnostic check by a service station and say that the Fuel Pump Power Control Module is not working. After checking the Internet I found a recall for this item on other GMC models but not the Acadia. There was no advance warning for the malfunction.

NHTSA complaint #11649694 — an unverified report by a vehicle owner.

ENGINE

I have had nothing but issues with this vehicle from the day I purchased it. I should have been more leery of purchasing a vehicle with so few miles on it as a certified vehicle. First issue lift gate wouldn’t work. Had to have sensors replaced twice. Next was the purge valve sensor that has went bad 3 separate times. Then the crankcase vent sensor. Paid a fee for diagnostics, it was not repaired took it back when the engine light came back on, they replaced it without charging but I was advised it’s not covered under warranty. And most recently my check engine light came on yet again today now reading an issue with the engine cooling system. Unfortunately the dealer is so booked out, my only option is to drop it off and hope they can get it in by a cancellation or no show. Seems there are new issues ever 3-6 months with the car.

NHTSA complaint #11648891 — an unverified report by a vehicle owner.

ENGINE

May 2023 we took the car to the GM dealership for a electronic recall. We reported a rattling noise at that point in time. Whatever repair was done that the car ran w/o any noise for nearly a year. April 2024 the catalytic converter failed at just 61K miles on this vehicle. The mechanic at the same dealership noted a broken mounting bracket and replaced the catalytic converter. October 24 2024 at 76K miles the car started making the same noise. The mechanic at the same dealership noted a loose mounting bracket due to an excessively vibrating catalytic converter, a crack on the cat converter, a leak and sequentially damaged front pipe. They noted they made all of those repairs. They noted they test drove the vehicle and verified the car was repaired. October 26, 2024 after those final repairs the car made a loud revving noise and emitted a smell of sulfur. The next day the car died on the road while driving. Every system of he vehicle shut down and I narrowly avoided getting hit from behind. On 11/2/24 We had the car towed to the dealership again. The mechanic noted the recent replacement on the cat converter & oil had leaked intermixing. That caused the motor to seize and the car to stop working while I was on the road driving. I can't imagine what could've happened to me had it stop on the highway at 65mph.

NHTSA complaint #11645736 — an unverified report by a vehicle owner.

ENGINE

Engine exhaust makes vibrating noise similar to a leaf blower under acceleration. TSB issued due to common issue and GM refuses to recall or fix. Broken baffle/weld inside of front muffler/resonator on exhaust system under front passenger compartment. Issue getting worse. $2500 at local dealership to fix, with GM offering “assistance” to fix issue in the amount of $742 leaving the consumer with balance. At what point will the rest of the defective part deteriorate and cause clogging issues and more damage?

NHTSA complaint #11628120 — an unverified report by a vehicle owner.

ENGINE

Vehicle stalled out and instrument panel showed no gas when the tank was over half full. I had trouble re-starting but was able to only drive a mile before stalling again. Both times occurred at a stoplight I had it towed to local dealer . They replaced the fuel pump power control module. The service personnel said that they see a large number of these and that some people had accidents due to this. I was about to enter a very busy highway at rush hour and if this happened on the highway, it would be very dangerous. I saw that there were previous recalls on GMC/Chevy vehicles similar to mine from 2021 that had recalls for this same reason but the Acadia has not been included. From what I have seen, a recall should be considered.

NHTSA complaint #11624343 — an unverified report by a vehicle owner.

ENGINE

The vehicle, without any warning, suddenly stopped. I was unable to restart and unable to put the vehicle in Neutral for pushing to a safer location. Had to be towed to the dealership.

NHTSA complaint #11604229 — an unverified report by a vehicle owner.

ENGINE

The car stopped working all of a sudden, I was driving the car with no issues that morning and parked & shut off car to go to my appt. I turned the car back on and worked fine as I was putting in my address on the GPS my car just stopped and shut off by itself. I pushed the start button and it sounded like it wanted to start but it wouldn't and the whole engine shooked. Called GM and car still under warranty had it towed to the nearest GM. They diagnosed it and said it was the fuel injector module that went bad. It's 2021 with only 23800 miles. After a week, just got it back for a day and now the cooling fan has a loud noise, check engine light on, coolant stays on C even after driving it more than 10 mins, ac blows hot air, I get an alert with steering assist is reduced and to drive with care.....seems like something is wrong with the thermostat.

NHTSA complaint #11550751 — an unverified report by a vehicle owner.

ENGINE

I have a really loud buzz & rattle noise. I can feel vibration on the passenger floor board real bad. The loud noise usually around 2,000-2,500 rpms. I have 39,000 miles on my car. It has always made a noise at take off but we thought it was normal untill now it's extremely worst. I took it into the dealship they diagnosed as something broken inside the muffler / resonator / weld inside muffler. So I did my research on the internet and I see alot of people complaining about this same issue on there cars. There was even a BULLETIN NUMBER (PIT5863) Pulished on 11/2/2021 the correction review # (21-na-118) all my issues are identical to bulletin. My year,make,model and issues with my car.

NHTSA complaint #11522455 — an unverified report by a vehicle owner.

ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL

The contact owns a 2021 GMC Acadia. The contact stated that while driving, he heard a loud rattling noise coming from the exhaust. The contact then stated that the RPM’s increased and the rattling noise became louder. No warning light was illuminated. The vehicle was taken to the dealer where it was diagnosed that the exhaust resonator failed the whole exhaust assembly needed to be replaced. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 28,000.

NHTSA complaint #11487664 — an unverified report by a vehicle owner.

ENGINE

car had only 5000 MILES . We live in denver took it to mountains for first time. we are both in our late 70 s . going down mouintains vail pass car engine EXPLODED CAR WENT INTO COMPLETE stop at highway speed. LUCKY WE DID NOT DIE as car went off to berm on i 70 west. milemarker 180 OR SO. GMC roadside called after 18 hours finally consented to tow car back to denver. we called 911 FOR FEAR OF OUR LIFE with trucks wheezing by. " GMC national" would not buy back car. my wife and I explained to gmc we were in a panic when this happened. DEALER AUTO NATION FOUND THAT pistons were blown up as well as engine. THEY OFFERED to give us new ?REBUILT engine .. we refused as we are very frightened to be in this car. DEALERSHIP FINALLY offered to buy car which we consented . GMC refuses to pay any of our trip interruptions expenses case no SR9-8150020854 april 1-866 790 5600 ext 5913625 PISTONS CONFRIMED BY AUTO NATION WEST GOLDEN CO TO BE DEFECTIVE AND SPONATEOUSLY BROKEN PISTONS THERE WAS DEFECT IN PRODUCTION OF PISTONS NO SAFETY WARNING THAT CAR ENGINE EXPLODED CAR JUST COMPLETELY STOPPED SUDDENLY

NHTSA complaint #11482254 — an unverified report by a vehicle owner.