2018 GMC Terrain Fuel system Problems

Gas leaking from the hood. High pressure fuel pump

NHTSA ID

11739681

Incident

May 22, 2026

Turbo boost went out in my vehicle and 3 others with the same engine, different makes/models. Vehicles were serviced at Grayling Car Care 4430 M-72, Grayling, MI 49738 (989) 348-3200. Significant power loss, sluggish acceleration, poor fuel economy, and often strange noises (whining, grinding), accompanied by blue smoke from burning oil and a lit check engine light, with the severe risk of catastrophic engine damage from broken parts entering the engine if driven, requiring prompt replacement. It's generally unsafe to drive with a bad turbo, as metal fragments can destroy the engine.

NHTSA ID

11714113

Incident

Jan 19, 2026

My check engine light comes on intermittently, since March 2024, after having Cabin & Engine air filters replaced. Each time, I’m told it is code P0171. This has happened too many times for my comfort. Usually, it happens around the time my gas gets below 1/2 tank or after I fill up my gas tank. Originally, I was told by the mechanic that it could be one of four things, of which I’ve now had some of things done. InIn Aug. 2024, the check engine light came in. Code was P0171. Mechanic replaced the Brake vacuum pump. Once incident, almost a month later, on 9/24/24, was very scary. While driving on the interstate, I got ready to increase my speed, but heard a pop sound and noticed the speed wouldn’t accelerate. Next, the check engine light came on and the message in the dash popped up saying “engine power reduced” or something similar. I was able to coast from the fast lane over to the slower lane and off the highway into a parking lot. I turned the truck off. When I crunk it back up an hour later, it was shaking and jerking. While slowly driving, on the way to the mechanic shop, it jerked and shook each time I tried to accelerate after stopping at a light or slowing down with traffic. The code again was P0171. According to the mechanic, the intake hose had popped off. On 11/13/24, the check engine light came on. I again took it to have the code scanned and truck looked at. Test results again showed P0171. This time the Mass Air Flow Sensor was suggested. In a year I’ve had the fuel system cleaned twice, brake system flushed, & other routine maintenance such as oil change & brakes. Yet, my check engine light seems to still come on intermittently atleast once monthly. It came on two days ago, 2/18/25, when my gas was around 1/4 tank full. I added a fuel system injector, per mechanic suggestion, and filled my tank up with gas on today, 2/20/25. The check engine light had gone off within about 15 mins of me driving. I’m certain it will be back on soon with the same code.

NHTSA ID

11644047

Incident

Mar 14, 2024

The contact owns a 2018 GMC Terrain. The contact stated while driving at approximately 65 MPH, the check engine warning light illuminated, and the vehicle decelerated to 20 MPH. Additionally, the message "Service Emissions" was displayed. The vehicle was taken to the local dealer who diagnosed that the diesel particulate filter was faulty and needed to be replaced. The vehicle was not yet repaired. The manufacturer was notified of the failure, but no assistance was offered. The contact was informed that the VIN was not included in the Extended Warranty coverage for the repair. The failure mileage was 26,000.

NHTSA ID

11631046

Incident

Sep 1, 2024

Mileage

26,000 mi

Hello. As I come to a complete stop the car will go into auto-stop. After releasing the brake pedal the car will jerk forward . As I press the gas pedal the car Jerks and shakes . The rpm jumps way up and the mph say low.. there's been times I try to accelerate and the car with jerk and put itself into park.. in the middle of traffic.. heart pounding to say the lease. I also notice theres alot of black liquid dripping for the front right side under the front bumper. There were no problems with the car or lamp indicating there were before this. I went to where I brought the car and they told me my warranty expired and that I will need to pay $265 just to diagnose the issue. I didnt have that money. I do have a car code reader and I did my best to find a solution. Codes P0700, P171D, And P187D all appear on my device. I then looked up recalls and my VIN wasn't confirmed.. but I am certain it is the same issue . You do have a open recall for this very particular issue for my particular model . I love my car and GMC. Please remedy this situation and have me driving safely and free minded again and soon ! Please reach back with any feedback as soon as possible. Thanks !

NHTSA ID

11607419

Incident

Aug 8, 2024

The contact owns a 2018 GMC Terrain. The contact stated that while driving at approximately 35 MPH going over a hill, the brake pedal was depressed but was firm and failed to depress as needed. The engine power reduced message was displayed and flashed on and then off. The brake assist warning light was illuminated. The service transmission message was displayed. The contact continued to depress the brake pedal until the vehicle responded as needed. The driver was able to pull into a parking lot, and the vehicle rolled to a stop. While driving, the engine misfired. Additionally, the vehicle failed to fully shutoff. The vehicle was towed to the local dealer, where it was diagnosed that the brakes had locked up and that the vacuum pump needed to be replaced. The contact was also informed that the cam shaft had fractured inside the engine. Additionally, the fuel injector, fuel line, and fuel pump needed to be replaced. The vehicle was not repaired. The contact related the failure to NHTSA Campaign Number: 19V645000 (Service Brakes, Hydraulic) and 23V013000 (Fuel System, Gasoline). The manufacturer was contacted, and the contact was informed that the VIN was under recall. The failure mileage was approximately 30,000.

NHTSA ID

11547673

Incident

May 1, 2019

Mileage

30,000 mi

The contact owns a 2018 GMC Terrain. The contact stated while driving approximately 30 MPH, the vehicle decelerated and failed to accelerate over 25 MPH while the accelerator pedal was depressed. The contact stated that a message was displayed on the instrument panel to “Continuously Drive Vehicle Above 30 MPH”. The contact stated that after the vehicle decelerated into engine power mode, the check engine warning light illuminated. The vehicle was taken to the dealer where it was diagnosed that the Diesel Particulate Filter (DPF) failed and needed to be replaced. Additionally, the contact stated that the vehicle was taken to the dealer twice where it was diagnosed that the Diesel Particulate Filter (DPF) needed to be unclogged. The vehicle was repaired; however, the failure recurred. The vehicle was not repaired. The manufacturer was notified of the failure and the contact was informed to contact the warranty company, but no further assistance was provided. The failure mileage was approximately 110,696.

NHTSA ID

11542629

Incident

Aug 28, 2023

Mileage

110,696 mi

My husband and son were involved in an almost fatal accident on 07/08/23 in our 2018 Terrain. My husband described that the vehicle spontaneously veered to the right uncontrollably, he was unable to steer to correct the vehicle, unable to brake, they went airborne, hit several poles and a transformer, rolled and flipped several times. All the airbags deployed.After the accident, I found a recall notice from back in 2017, I believe, regarding the drive train. My husband was extricated from the vehicle. My son wasble to cut the seatbelt and crawl out the window. From what my husband explained (he was the driver), this sounds like what they experienced during the collision. I never received a recall letter from GM as this is something I would of taken care of and have got repaired. Please see the photos and the recall I found. Please let me know if there is anyone else I need to contact regarsing this collision.My car was almost paid off. My husband and son could of lost their life. Please advise. Thank you!

NHTSA ID

11531130

Incident

Jul 8, 2023

1. 2018 Terrain would not start in a parking lot. Remote was used after several attempts to start with push button failed, and after a slight hesitation , engine started. Vehicle was driven about 6 miles without incident. 2. Vehicle was driven about 10 miles the next day and start/stop engaged at a stop light but would not restart. After about 3 minutes of cycling throught the starting procedure, the vehicle started. Drove another 8 miles without incident. 3. Next morning, drove about 3 miles to intersection where start/stop engaged but would not restart. After about 30 minutes of cycling through starting procedure and an attempt to jump start was made the vehicle restarted. At this point, the vehicle was taken to Romain GMC for service. A new battery was installed and other related operations.After about 10-15 miles, the vehicle would not start. Remote was attempted but it would not start. After about an hour, vehicle started and was driven back to Romain avoiding the stop/ start engagement.

NHTSA ID

11460372

Incident

Apr 1, 2022

Catalytic converter failed when driving damaging the engine. Vehicle undrivable and waited for repair at shop for over 90 days. Engine warning light keeps coming on with error code P1186 that the GMC dealer can not fix.

NHTSA ID

11444179

Incident

Sep 12, 2021

Yesterday morning I noticed a smell of gas around my car. I looked and didn’t see anything. I drove to work. Once I got back to my vehicle after work I could smell gas as I approached my vehicle. I looked under my car and noticed a puddle of gas. I went to the gas station to put enough fuel for me to make it home in my vehicle and as I was putting the gas I noticed a drip under the vehicle. Once I got home and parked my vehicle I looked under the car and there was a rapid and steady drip coming from the fuel tank. The same make, mode and year of my vehicle has been recalled for this.

NHTSA ID

11435997

Incident

Oct 7, 2021

SCREEN WENT BLACK AND WARNING CHIMES AND SEAT VIBRATION DID NOT GO OFF WHEN BACKING UP. HAD TO FILE A CLAIM WITH INSURANCE TO FIX MY DENTED BUMPER. I ALSO EXPERIENCE ISSUES WITH THE AUDIO BUTTONS ON THE STEERING WHEEL. I AM NOT ABLE TO CHANGE THE SONG IN I AM ON APPLE PLAY AND THERE IS ALWAYS A DELAY WHEN CHANGING RADIO STATIONS.

NHTSA ID

11270218

Incident

Jul 12, 2019

Mileage

27,000 mi

MY VEHICLE HAS BEEN MAKING A NOISE EVERY SINCE THE DAY OF PURCHASE. IT STARTED AS A VAGUE SOUND AND HAS SINCE GOTTEN WORSE. THE NOISE IS COMING FROM THE REAR EXHAUST. AT CERTAIN SPEEDS OF TRAVEL THE NOISE GETS WORSE. I HAVE DONE A VISIBILITY CHECK OF THE REAR EXHAUST PIPE AND NOTICED THE ASSEMBLED EXHAUST WHERE IT WAS WELDED IS LOOSE AND SHAKING. I'M NOT FOR SURE IF THIS IS WHERE THE NOISE IS COMING FROM BUT IT COULD USE SOME INVESTIGATION. I PURCHASED MY VEHICLE WITH NO MILEAGE ABOUT 5 MONTHS AGO FROM HENNESSY GMC IN MORROW GEORGIA.

NHTSA ID

11176213

Incident

Aug 18, 2018

Mileage

21 mi

LEAKING DIESEL FUEL LINE WHILE RUNNING, PARKED AND IN GEAR. SECOND DIESEL TERRAIN FLEET VEHICLE TO LEAK FUEL; OTHER COLLEAGUE HAD THE SAME ISSUE RECENTLY AND WAS ASKED IF SOMEONE CUT THE FUEL LINE. NOW, MINE IS LEAKING.

NHTSA ID

11152349

Incident

Nov 18, 2018

Mileage

15,100 mi

THIS CAR, A 2018 GMC TERRAIN IS EQUIPPED WITH AUTO START / STOP, A STANDARD FEATURE THAT TURNS OFF THE ENGINE WHEN BRAKE IS APPLIED, SUCH AS AT A STOP LIGHT. THE ENGINE TURNS OFF WHILE BRIEFLY STOPPED AT A STOP SIGN. THIS IS DANGEROUS AND A SAFETY ISSUE. WHILE ATTEMPTING TO PULL INTO A TRAFFIC LANE WITH THE ENGINE OFF, I HAVE EXPERIENCED AN UNSAFE LAG BEFORE THE ENGINE RESTARTS. GM HAS STATED, THE ENGINE CAN BE TURNED BACK ON BY REMOVING YOUR FOOT BRIEFLY FROM THE BRAKE PEDAL. SERIOUSLY ??? WHILE BEHIND ANOTHER VEHICLE, I WILL NOT FOLLOW THIS PROCEDURE. I HAVE NO CONFIDENCE THE ENGINE WILL RESTART AND LUNGE FORWARD, STRIKING THE VEHICLE AHEAD. I WANT GM TO PROVIDE THE CAPABILITY TO PROVIDE THE DRIVER THE ABILITY TO ENABLE OR DISABLE AUTO START / STOP. THE FEATURE IS ALSO TOUTED AS SAVING FUEL WHILE STOPPED. PERHAPS A TINY AMOUNT WHILE AT A LONG LIGHT OR TRAIN CROSSING. CERTAINLY NOT AT A STOP SIGN OR STOPPED BEHIND ANOTHER VEHICLE.

NHTSA ID

11062141

Incident

Jan 4, 2018

Mileage

248 mi