There are 3 stored owner reports matching the engine leading-label group for the 2018 Buick LaCrosse in our NHTSA-sourced dataset. These are unverified consumer reports and may not reflect confirmed defects.
This group counts stored reports whose component label starts with one of this site's matching prefixes, ignoring case. Each matching report counts once within the group. Components mentioned later in the label or only in the narrative are not searched. How component counts work
Loaded 3 of 3 matching reports.
Open the full vehicle complaint log (all categories)The 3.6 liter engine in my 2018 Buick Lacrosse Avenir only has 53,939 when we experienced a thermostat failure. The engine temperature was dead cold, and the dual electric fans were running non-stop. When I scanned the trouble code, I found PO128 which points to a faulty thermostat. Because the thermostat is buried under the intake manifold, we had the local Buick dealership replace it at a cost of over $800.00. I don't feel that a car with so few miles should be experiencing a thermostat failure. But this seems to be a common problem with the GM 3.6 liter motor according to a number of Buick forums that I read after the problem occurred.
Thermostat failure at 56,000 miles.
IF STOPPED UPHILL AND THE AUTO STOP ACTIVATES, WHEN YOU RELEASE THE BRAKE THE CAR CAN ROLL BACK, AND THE WAY PEOPLE STOP ON TOP OF YOU THESE DAYS YOUR CAR CAN ROLL BACK INTO THEM AND YOU HAVE TO REPAIR THEIR CAR. PLUS IT ACTUALLY TAKES MORE GAS THAN MY V8 2016 GMC SIERRA THAT DOESN'T STOP WHEN TRAVELING FROM MY FUELING LOCATION TO MY HOME, PER THE CARS OWN COMPUTER SYSTEM
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
NHTSA source checks for this vehicle year
Checks are recorded separately for each dataset, not for the whole page. Dates use UTC. A missing check date does not mean no records exist.
Vehicle import recorded: Apr 28, 2026. This is the stored import date, not confirmation that every source was successfully refreshed.