2018 Buick Encore: check engine light

Filed Nov 2, 2026 · Engine · 55,753 miles · MN

The contact owns a 2018 Buick Encore. The contact stated that while driving, the vehicle ran rough and sputtered. The check engine warning light failed to illuminate following a deep cleaning service. The vehicle was taken to the dealer for inspection and repair. The dealer identified software failures associated with DTC: P162B and DTC: P111E, and performed software updates. The contact stated that a leak occurred in the positive crankcase ventilation (PCV) system associated with DTC: P0171. The dealer replaced the intake manifold, vapor canister purge valve, and PCV component, stating that no leaks were found during the inspection. The contact had the removed parts inspected by an independent mechanic, who found an internal leak. The contact stated that the OnStar system indicated that the check engine warning light was illuminated, and an abnormal exhaust odor emanated from the vehicle. While driving, the driver experienced drowsiness and expressed concern regarding carbon monoxide exposure. The contact stated that the tailpipe was damaged and expressed concern regarding warranty coverage for the turbocharger and catalytic converter. The manufacturer was notified of the failure regarding DTC: P0029, but declined warranty coverage. The contact believed that the failures were associated with Special Coverage Programs: N232395320 and N192211170. Although repairs and software updates were performed, the contact remained concerned that the underlying mechanical failures were not properly diagnosed or resolved, and that PCV, turbocharger, and exhaust failures caused reduced engine performance, cabin exhaust fumes, and risk of carbon monoxide exposure. The failure mileage was approximately 55,753.

Filed Aug 2, 2026 · Engine, Fuel system · NC

Not long after I purchased my car, i noticed it was lacking power during takeoff and when driving uphill which forced my car to hit very high RPMs during normal use. There was also a P0299 code that appeared then disappeared frequently. I discovered a turbo special coverage N232395330 and took it to Williams GMC in Charlotte. After i told them very clearly what happened MULTIPLE times, confirming the underboost and the code, I even brought it in with the code, they told me the code wasnt "active" and that there no problems...even after i told them I didnt feel safe and couldnt pull out at intersections with fear of being rear-ended. I had videos, they refused to look at and told me to come back when the code was permanent. I drove the vehicle for the next year, 20k miles in order to get the code permanent, after a trip home, through the mountains, really tough without the turbo, my car was consistently pinging 4-5000 RPM under the speed limit on inclines...this happened every time I drove through, but this time the code was active the entire time. 2-3000 miles with the code, finally it was permanent. I brought the car back to Williams GMC, to get the turbo changed. I updated them on recent occurrences, flashing check engine light, the code active for 2-3k miles, and they performed a road test, and declared it wasn't a problem. I told them i recently spent 5k on repairing my cooling and AC system because the turbo, they said that wouldn't affect those components, meanwhile i know they have plastic parts that can melt and the engine being forced to push 4-5k RPM the extra heat could easily melt those parts. They said, nothing was wrong and the road test was good. sent me on my way. I called corporate, they told me to get a second opinion. I did [XXX] found the problem and changed the turbo per the special coverage N232395330. a week later, my engine overheated, i pulled over and it wouldnt start, engin won't hold compression. Car is tot now. Long story shrt INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORM

Filed Jul 31, 2026 · Engine · NH

General Motors issued a Special Policy N202299080 covering 2014 Buick Encores. My 2018 Encore had the same issues and symptoms as this Policy. My concern is because of this known problem the crankcase can be pressurized causing oil leaks which could cause a fire. General Motors issued a Service Information Bulletin 19-NA-114 in May 2019 about involving 2013 to 2019 Buick Encores. This is a known issue for many models other than my vehicle. I have the old parts from the repair for inspection which includes the Intake Manifold and the Valve Cover for faulty PCV components that cause the engine to produce excess Engine Crankcase pressure possibly causing a fire. My vehicle had a check engine light code of P0171 and the odor of burning oil.

Filed Jun 10, 2026 · Engine · PA

Request for Goodwill Assistance – Turbocharger Failure (Special Coverage XXX) Dear General Motors Customer Assistance, I am writing to request a one-time goodwill repair for my 2018 Buick Encore (VIN: [XXX]). Approximately two months after purchasing this vehicle, the check engine light illuminated and diagnostic testing identified code P0299, indicating turbocharger failure. This issue appears to align with General Motors' Special Coverage Program XXX, issued in February 2024 for certain 2017–2018 Buick Encore vehicles equipped with the 1.4L engine due to known turbocharger failures. Unfortunately, my local GM dealership has informed me that they are unable to perform the repair under the special coverage because the vehicle carries a Pennsylvania reconstructed (R) title. While I understand the vehicle's title status, I respectfully ask GM to consider the unique circumstances. In Pennsylvania, reconstructed vehicles must undergo a rigorous Enhanced Vehicle Inspection process before they can be legally registered and operated on public roads. My vehicle successfully passed all required inspections and is legally certified for highway use. Because this special coverage was issued to address a defect that may lead to significant engine damage and, in some cases, a potential engine compartment fire, I am requesting a one-time goodwill repair or other assistance from General Motors. The concern involves a known condition affecting this vehicle platform and presents a potential safety risk during both local and highway driving. I have been a loyal GM customer and would greatly appreciate your review of this situation. Given that the vehicle has been properly repaired, inspected, and approved for road use under Pennsylvania law, I respectfully request that GM reconsider eligibility for assistance despite the reconstructed title designation. Thank you for your time, consideration, and any assistance you may be able to provide. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B

Filed Nov 10, 2025 · Engine · 98,507 miles · OH

The contact owns a 2018 Buick Encore. The contact stated that while driving at an undisclosed speed, the vehicle inadvertently lost motive power. The contact 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 taken to the dealer, who diagnosed a failure with the timing chain, resulting in damage to the crankshaft. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 98,507.

Filed May 30, 2025 · Engine · 109,800 miles · FL

The contact owns a 2018 Buick Encore. The contact stated while driving at undisclosed speeds, the vehicle was shaking abnormally with the check engine and stabili-trak warning lights illuminated. The contact pulled over to the side of the road and turned off and restarted the vehicle and the warning lights were cleared, and the vehicle drove normally. The contact stated that the failure was intermittent but was a recurring failure. The contact had taken the vehicle to an independent mechanic who diagnosed the vehicle and replaced the ignition coils and spark plugs; however, the failure reoccurred. The manufacturer was informed of the failure and referred the contact to the federal safety agency Hotline. The failure mileage was approximately 109,800.

Filed Jan 10, 2025 · Engine · MI

I have been alerted by General Motors, via a letter that I received in March, 2024, that, due to a defect, my car's (a 2018 model year Buick Encore) engine may have a "condition where the turbocharger could fail" and that "the engine may run rough or have reduced power." In the letter, they have offered "additional protection for the condition" if the "condition occurs...within 10 years of the date your car was originally placed in service or 120,000 miles...whichever occurs first." On [XXX], my car was at 126,819 miles, and had all of the symptoms of the issue that were described in the March 2024 letter ("the Malfunction Indicator Light (Check Engine Light) will illuminate and a diagnostic trouble code will set. Additionally, the engine may run rough or have reduced power.") On May 3, 2024, I contacted GM at the phone number provided in the March 2024 letter ((800) 521-7300.) I was told by the GM representative that, because I was "over the mileage", that any GM dealer would have to charge me a $130.00 Diagnostic Fee to diagnose the issue, and, that even after diagnosing, there was no guarantee that GM would fix the issue, because I was "over the mileage". The GM representative also said I could ask the dealer to waive the Diagnostic Fee, at the dealer's discretion. If, after paying the Diagnostic Fee, and if the Diagnostic Fee revealed that my car did have the "turbocharger fail condition", that I could THEN contact GM to see IF they would cover the repair cost. In May, 2024, my car was at about 128,000 miles. I contacted two GM dealers: Les Stanford Buick in Ferndale, MI, and James Martin Chevy in Detroit, MI. Both refused to waive the Diagnostic Fee. So, in other words: - GM has created a defective, potentially DANGEROUS product, that GM acknowledges is defective. - GM created a warranty extension in which GM arbitrarily extended the warranty mileage and time. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Dec 7, 2024 · Engine · NJ

Overdrive recall and check engine lights is on. We were just informed about the recall from our mechanic

Filed Sep 18, 2024 · Engine, Fuel system · LA

Stalling and shuts off. Low power when accelerating. Car has been so slow to take off that when merging into on coming traffic I have to move to shoulder & then try again to prevent an accident. Coughs, putt & squeaking sounds.Car shakes while in park or not in motion. Check engine light on.

Filed Sep 4, 2024 · Engine · MI

There are many Buick Encores, including 2018 that have a problem with acceleator position sensors. My car’s vin # shows that it does not have this notice, and thus no problem. However, in July this 2018 Buick Encore went into ‘limp mode, check engine light came on. Code for problem was 2138 (accelerator Pedal Position Sensor) The initial dealer solution was to apply dielectric grease. However, this ‘cure’ lasted . 15 miles, when it went into limp mode,,, again check engine icon came on THIS is very dangerous, as it cannot accelerate and from a stop, it does not move until a minute later… that is so frightening, I again took it to the deaer, same code of P2138, and now they recommend the accelerator pedal positon sensor replacement…. THIS is identical to the problems with the other Encores, This is a severe safety issue, and the rest of the 2018 Buick Encores should be included for notification AND repair .

Filed Aug 9, 2024 · Brakes, Engine · 20,000 miles · FL

The contact owns a 2018 Buick Encore. The contact stated that while driving at an undisclosed speed, the vehicle lost motive power, power steering, and brake functionality. The vehicle began to shake, and the brakes and steering wheel became inoperable. The check engine warning light was illuminated. The vehicle was taken to the local dealer, who was unable to determine the cause of the failure. The vehicle was not diagnosed or repaired. The vehicle was taken back to the local dealer, where the mechanic test drove the vehicle but was unable to duplicate the failure. While driving, the fan failed to turn off. The vehicle was taken to the local dealer Orange Buick GMC (3883 W Colonial Dr, Orlando, FL 32808), where it was diagnosed that the coil and relay needed to be replaced. The vehicle was repaired, but the failure recurred. The contact stated that while driving the vehicle failed to accelerate above 65 MPH. The brake pedal was depressed but the vehicle failed to respond. The vehicle was taken back to another local dealer, Gettel Chevrolet Buick GMC (1901 Tamiami Trl, Punta Gorda, FL 33950), where it was diagnosed that the fan, relay, and spark plugs needed to be replaced. The vehicle was not repaired. The manufacturer was contacted and informed the contact about repairing the vehicle and the process for reimbursement. The failure mileage was approximately 20,000. The VIN was not available.

Filed Aug 6, 2024 · Engine · ND

Turbo charger has A leak, dealer stated they knew it had a leak but they couldn't find it. All they did was clear the code. My car has A check engine light, and a trouble code of PO299, does not maintain proper speed, has issues with acceleration.