When sitting at idle, the engine miss & spark knock at times. When start driving down the road the throttle seems hard to Press & takes a little time to reach up to road speed. The truck does not get good gas mileage at all. I had the spark plugs & wires changed still don't help.
NHTSA complaint #11744895 — an unverified report by a vehicle owner.
Coolant leak observed at the upper radiator hose quick-connect fitting. The leak appears to originate from the internal seal at the radiator inlet connection. This issue developed without warning and is consistent with a known defect in the radiator hose seal design used in 2023 GMC Canyon vehicles. Vehicle experienced coolant loss and visible residue at the connection point. No visible external damage to the radiator or hose assembly was observed. GM has issued a Special Coverage program for similar radiator inlet hose seal failures in related vehicles using the same component design. Concern is that this defect may lead to coolant loss and potential engine overheating if not addressed.
NHTSA complaint #11733035 — an unverified report by a vehicle owner.
The engine coolant temperature sensor has failed on my 2019 GMC Canyon. The check engine light is illuminated, the temperature gauge does not register correctly, the air conditioning has been disabled by the vehicle's computer, and the engine cooling fan continues to run after the engine is turned off. These symptoms are consistent with the vehicle entering fail-safe mode due to loss of a valid coolant temperature signal. The problem was confirmed by an independent mechanic who diagnosed a failed coolant temperature sensor. The mechanic attempted to source a replacement part through GMC but was informed the part was unavailable. The reason for the parts unavailability is unknown, though in his experience, it typically means that the manufacturer is stocking up and preparing for a recall This issue appears to be widespread across 2017–2020 GMC Canyon and Chevrolet Colorado V6 trucks based on extensive owner forum documentation. The safety concern is significant: without reliable coolant temperature monitoring, there is no assurance the engine is operating within safe thermal limits, and the driver has no warning if overheating occurs. The disabled A/C also creates a safety risk during periods of extreme heat. The vehicle has approximately 60,000 miles. The problem has been present for approximately three months and is ongoing.
NHTSA complaint #11731109 — an unverified report by a vehicle owner.
Coolant leak caused by known manufacture defect in upper hose assembly causes coolant to drain and engine to overheat. CEL only comes on when coolant is almost gone. GMC refuses to cover the known issue after 36k miles.
NHTSA complaint #11722976 — an unverified report by a vehicle owner.
Coolant Leaking at 22K miles, smell of coolant, check engine light on and off 2X's. Coolant evidence on driveway and in engine cabin. Known condition for GM Model. No parts available for replacement. No recall for issue.
NHTSA complaint #11722659 — an unverified report by a vehicle owner.
Upper radiator hose connection to radiator is faulty causing leak of coolant. Yes it is available for inspection upon request. Truck began to run cooling fan at full speed in the middle of winter with no warnings of high heat or low coolant. After two weeks, check engine light finally cut on to indicate low coolant flow. Coolant reservoir was subsequently checked and found to be completely empty. It is apparent this reservoir had been extremely low / empty for at least two weeks with no warnings. Without proper warning and leaking coolant, truck could have overheated. Should this had happened in dead of summer, truck could have very well overheated with no warning. The problem was investigated and confirmed by dealer as leaking coolant at the connection of the upper radiator hose to the radiator. Was quoted $983 to replace the hose. No warning lights appeared until issue had been ongoing for over two weeks. A quick search of "GMC Canyon Upper Radiator Hose" will reveal many identical occurrences of this issue. This is a safety hazard / design flaw that GM is not acknowledging and is putting the burden on the vehicle owners for their own issue.
NHTSA complaint #11721052 — an unverified report by a vehicle owner.
The upper radiator hose on some huge percentage of these trucks fail (mine has failed at just over 37K miles). You can check the Colorado Chevy and GMC Canyon forums, youtube, Facebook, etc., et al, and find plenty of instances where this has failed. As this is the cooling system, it can cause the engine to overheat and potentially ruin the engine. The flaw seems to be an engineering issue with the rubber seal they use (instead of a high quality o-ring) to seal the upper hose to the radiator. Additionally, since this can cause engine failure it should be addressed immediately. Instead, my local Chevy dealer, since its not a recall item, said they could schedule a time next week for me to LEAVE the truck and that I am responsible for the repair. This is extremely unfair to the consumer who depends on these vehicles. This should absolutely be a recall item. You can find 1000's of examples online and if you can pull GM repair data, I'm sure you'll find 1000's more.
NHTSA complaint #11720437 — an unverified report by a vehicle owner.
On 2 occasions the battery was drained and a tow truck had to jump the battery. On one occasion after the battery was jump started it took several hours before the brakes were able to be used and the car driven safely. Had to drive very slowly (under 50 mph) per note that appeared on dashboard. After nearly an hour of waiting Engine light stayed on and dealership ran diagnostic and found nothing wrong with the battery nor anything else. Have to start and run engine everyday to keep battery from dying. If not started in 24 to 36 hours, battery will die.
NHTSA complaint #11718011 — an unverified report by a vehicle owner.
There are widespread reports of the O ring seals on the radiator and heater hoses failing and causing coolant leaks. These leaks are significant enough to render the vehicle inoperable and with no cabin heating or cooling. This could lead to life-threatening situations in adverse weather conditions. It could also create dangerous roadside failure situation in heavy traffic, particularly on interstate highways. Dealers are aware of the issue and are currently repairing vehicles under warranty. However some dealers are telling owners that the cooling system is not part of the engine and drivetrain, and therefor is not covered under the original factory warranty if the vehicle has exceeded the initial bumper to bumper warranty limits. Dealers are also telling owners that parts are on backorder due to high demand, and that repair wait times could take weeks. The vehicle is unsafe to operate with a known coolant leak. Video of leak (another owner) here. [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11711833 — an unverified report by a vehicle owner.
Upper radiator hose attachment is leaking due to faulty rubber gasket. This comes up across GMC Canyon groups on Facebook 10 times a day. It is happening to ALL of them mainly pre 2025 on 3rd gens. Part is on back order at all GMC dealers due to so much volume of issue. Happening as early as 10k-20k miles on brand new trucks causing over heating issues due to coolant leaking out. Hopefully a recall for the part is done before engines start blowing.
NHTSA complaint #11711886 — an unverified report by a vehicle owner.
Truck began idling very rough. Went straight to the dealership. They shut the truck off and it would not restart. No CEL or messages on the dash. Tear down reveled a failed exhaust valve in cylinder #4. Truck has 10,000 miles. A replacement engine has been ordered under warranty. Luckily, we happened to only be a few miles from a dealership when the failure happened. There was no warning, no prior symptoms what so ever.
NHTSA complaint #11710979 — an unverified report by a vehicle owner.
The contact owns a 2025 GMC Canyon. The contact stated that while the vehicle was parked, the contact discovered a coolant leak underneath the front of the vehicle. No warning lights were illuminated. The vehicle was taken to a dealer to be diagnosed; however, the vehicle had not yet been diagnosed. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 13,500.
NHTSA complaint #11708852 — an unverified report by a vehicle owner.
Noticed a coolant leak on drivers side and took to dealership was told was the upper radiator hose but was unable to make repairs due to national backorder and only suggestion was to drive until parts come in and keep a check on the coolant level, My truck only has 28,708 miles and shouldn't have to keep an eye on coolant level I feel that is very unsafe
NHTSA complaint #11705901 — an unverified report by a vehicle owner.
The upper radiator hose on a significant number of these trucks is failing prematurely. In my case, the failure occurred at just over 35,000 miles. Numerous reports on owner forums (such as the Colorado Chevy / GMC Canyon forum), YouTube, and other platforms document the same issue, indicating this is not an isolated incident but a widespread defect. Because this hose is part of the cooling system, its failure can quickly lead to engine overheating and potentially catastrophic engine damage. The root cause appears to be an engineering flaw in the sealing method: GM uses a rubber seal instead of a durable, high-quality o‑ring to connect the upper hose to the radiator. Despite the seriousness of this defect, my local GMC dealer informed me that—since it is not currently a recall item—they could only schedule service for the following week, requiring me to leave the truck with them for 7–10 days before repairs would be completed. This is unreasonable for consumers who rely on these vehicles daily. Given the safety implications and the potential for engine failure, this issue warrants immediate attention. It should be classified as a recall item. Thousands of examples are already documented online, and GM’s own repair data would likely reveal thousands more instances of this same failure.
NHTSA complaint #11703623 — an unverified report by a vehicle owner.
I've noticed an issue since I picked up my vehicle from its last service where the RPMs stay around 1,000 when I let off the gas and should be coasting. The vehicle will continue to accelerate at 11 to 13 mph, and I really have to mash the brake pedal to stop. There is an update notice that popped up starting yesterday, but it will not install. Looks like the update is for the issue I am having. The update was supposed to be installed already per the service bulletin. Update number is N242452130
NHTSA complaint #11698266 — an unverified report by a vehicle owner.